Megaprime
A megaprime is a prime number with at least one million decimal digits.[1]
Other terms for large primes include titanic prime, coined by Samuel Yates in the 1980s for a prime with at least 1,000 digits, and gigantic prime for a prime with at least 10,000 digits. Bevaprime has been proposed for a prime with at least 1,000,000,000 digits.[2]

As of 2022, there are more than 1000 known definite megaprimes[3] and 78 probable primes (PRPs) which have more than 1,000,000 digits.[4] The first to be found was the Mersenne prime 26972593−1 with 2,098,960 digits, discovered in 1999 by Nayan Hajratwala, a participant in the distributed computing project GIMPS.[5][6] Nayan was awarded a Cooperative Computing Award from the Electronic Frontier Foundation for this achievement.
Almost all primes are megaprimes, as the number of primes with fewer than one million digits is finite. However, the vast majority of known primes are not megaprimes.
All numbers from 10999999 through 10999999 + 593498 are known to be composite, and there is a very high probability that 10999999 + 593499, a strong probable prime, is the smallest megaprime.[7] As of 2022, the smallest number to be known as a megaprime is 10999999 + 308267*10292000 + 1.
The last prime that is not a megaprime is almost certainly 10999999 - 172473.[4]
Known megaprimes and mega PRPs
Entries labelled "Prime" have been proved prime; those labelled "PRP" have not, and primes that have not been fully verified by PrimePages will be ranked, but be listed as a PRP. See the article Probable prime. Only primes with more than 2,000,000 digits are included in this list.
Rank (only for proven primes)[8] | Number | Discovery date | Decimal digits | Prime / PRP |
---|---|---|---|---|
1 | 282589933 – 1 | 7 December 2018 | 24,862,048 | Prime |
2 | 277232917 – 1 | 26 December 2017 | 23,249,425 | Prime |
3 | 274207281 – 1 | 7 January 2016 | 22,338,618 | Prime |
4 | 257885161 – 1 | 25 January 2013 | 17,425,170 | Prime |
5 | 243112609 – 1 | 23 August 2008 | 12,978,189 | Prime |
6 | 242643801 – 1 | 4 June 2009 | 12,837,064 | Prime |
7 | 237156667 – 1 | 6 September 2008 | 11,185,272 | Prime |
8 | 232582657 – 1 | 4 September 2006 | 9,808,358 | Prime |
9 | 10223×231172165 + 1 | 31 October 2016 | 9,383,761 | Prime |
10 | 230402457 – 1 | 15 December 2005 | 9,152,052 | Prime |
- | 8 May 2021 | 8,177,207 | PRP | |
11 | 225964951 – 1 | 18 February 2005 | 7,816,230 | Prime |
12 | 224036583 – 1 | 15 May 2004 | 7,235,733 | Prime |
13 | 202705×221320516 + 1 | 25 November 2021 | 6,418,121 | Prime |
14 | 220996011 – 1 | 17 November 2005 | 6,320,430 | Prime |
15 | 10590941048576 + 1 | 4 November 2018 | 6,317,602 | Prime |
16 | 9194441048576 + 1 | 2 September 2017 | 6,253,210 | Prime |
17 | 168451×219375200 + 1 | 26 September 2017 | 5,832,522 | Prime |
- | 20 April 2021 | 5,794,777 | PRP | |
18 | 3×218924888 - 1 | 25 March 2022 | 5,696,990 | Prime |
19 | 69×218831865 - 1 | 16 December 2021 | 5,668,959 | Prime |
20 | 7×218233956 + 1 | 1 October 2020 | 5,488,969 | Prime |
21 | 3×218196595 - 1 | 18 January 2022 | 5,477,722 | Prime |
22 | 3×217748034 - 1 | 6 September 2021 | 5,342,692 | Prime |
23 | 23 February 2017 | 5,338,805 | Prime | |
24 | 3622×57558139 - 1 | 18 February 2022 | 5,282,917 | Prime |
25 | 7×66772401 + 1 | 9 September 2019 | 5,269,954 | Prime |
26 | 8508301×217016603-1 | 22 March 2018 | 5,122,515 | Prime |
27 | 3×216819291-1 | 20 January 2021 | 5,063,112 | Prime |
28 | 3×216408818+1 | 28 October 2020 | 4,939,547 | Prime |
29 | 69×215866556+1 | 20 August 2021 | 4,776,312 | Prime |
30 | 2525332×732525332+1 | 28 August 2021 | 4,705,888 | Prime |
31 | 215317227+27658614+1 | 31 July 2020 | 4,610,945 | Prime |
32 | 6×56546983+1 | 13 June 2020 | 4,576,146 | Prime |
- | June 2021 | 4,556,209 | PRP | |
33 | 69×214977631-1 | 3 December 2021 | 4,508,719 | Prime |
34 | 192971×214773498-1 | 7 March 2021 | 4,447,272 | Prime |
35 | 6962×312863120-1 | 29 February 2020 | 4,269,952 | Prime |
36 | 99739×214019102-1 | 25 December 2019 | 4,220,176 | Prime |
37 | 69×213832885-1 | 17 January 2022 | 4,164,116 | Prime |
38 | 404849×213764867+1 | 10 March 2021 | 4,143,644 | Prime |
39 | 2740879×213704395-1 | 26 October 2019 | 4,125,441 | Prime |
40 | 479216×38625889-1 | 16 November 2019 | 4,115,601 | Prime |
41 | 30 January 2017 | 4,055,114 | Prime | |
42 | 213466917 – 1 | 14 November 2001 | 4,053,946 | Prime |
- | 213380298 – 27 | March 2021 | 4,027,872 | PRP |
- | September 2013 | 4,025,533 | PRP | |
- | September 2013 | 4,017,941 | PRP | |
43 | 9×213334487 + 1 | 31 March 2020 | 4,014,082 | Prime |
44 | 206039×213104952 - 1 | 26 April 2021 | 3,944,989 | Prime |
45 | 2805222×55610444 + 1 | 3 September 2019 | 3,921,539 | Prime |
46 | 19249×213018586 + 1 | 26 March 2007 | 3,918,990 | Prime |
47 | 2293×212918431 - 1 | 13 February 2021 | 3,888,839 | Prime |
- | July 2020 | 3,763,995 | PRP | |
48 | 9×212406887 + 1 | 29 March 2020 | 3,734,847 | Prime |
49 | 69×212231580 - 1 | 27 July 2021 | 3,682,075 | Prime |
50 | 27*212184319 + 1 | 6 February 2021 | 3,667,847 | Prime |
51 | 3×211895718 − 1 | 26 June 2015 | 3,580,969 | Prime |
52 | 3×211731850 − 1 | 13 March 2015 | 3,531,640 | Prime |
53 | 69×211718455 − 1 | 4 December 2020 | 3,527,609 | Prime |
54 | 69×211604348 − 1 | 4 December 2020 | 3,493,259 | Prime |
55 | 9×211500843 + 1 | 13 March 2020 | 3,462,100 | Prime |
56 | 3×211484018 − 1 | 22 November 2014 | 3,457,035 | Prime |
57 | 193997*211452891 +1 | 3 April 2018 | 3,447,670 | Prime |
58 | 3638450524288 +1 | 31 May 2020 | 3,439,810 | Prime |
59 | 9221*211392194 -1 | 7 February 2021 | 3,429,397 | Prime |
60 | 9*211366286 +1 | 26 March 2020 | 3,421,594 | Prime |
61 | 5*211355764 -1 | 2 October 2021 | 3,418,427 | Prime |
62 | 3214654524288 +1 | 25 December 2019 | 3,411,613 | Prime |
63 | 146561*211280802 -1 | 17 November 2020 | 3,395,865 | Prime |
64 | 2985036524288 +1 | 19 September 2019 | 3,394,739 | Prime |
65 | 2877652524288 +1 | 29 June 2019 | 3,386,397 | Prime |
66 | 2788032524288 +1 | 18 April 2019 | 3,379,193 | Prime |
67 | 2733014524288 +1 | 19 March 2019 | 3,374,655 | Prime |
68 | 9*211158963 +1 | 13 March 2020 | 3,359,184 | Prime |
69 | 9271*211134335 -1 | 17 January 2021 | 3,351,773 | Prime |
70 | 2312092524288+1 | 5 August 2018 | 3,336,572 | Prime |
71 | 2061748524288+1 | 21 March 2018 | 3,310,478 | Prime |
72 | 1880370524288 + 1 | 15 January 2018 | 3,289,511 | Prime |
73 | 27×210902757 - 1 | 7 March 2022 | 3,282,059 | Prime |
74 | 3×210829346 + 1 | 14 January 2014 | 3,259,959 | Prime |
75 | 5×210495620 - 1 | 26 September 2021 | 3,159,498 | Prime |
- | 9 July 2020 | 3,143,811 | PRP | |
76 | 5×210349000 - 1 | 26 September 2021 | 3,115,361 | Prime |
77 | 17 January 2017 | 3,107,335 | Prime | |
78 | 14 January 2017 | 3,068,389 | Prime | |
79 | 874208*541748416-1 | 26 September 2019 | 3,028,951 | Prime |
80 | 475856524288 + 1 | 8 August 2012 | 2,976,633 | Prime |
81 | 9*29778263+1 | 5 August 2020 | 2,943,552 | Prime |
82 | 1806676*411806676+1 | 12 March 2018 | 2,913,785 | Prime |
83 | 356926524288 + 1 | 25 July 2012 | 2,911,151 | Prime |
84 | 341112524288 + 1 | 25 June 2012 | 2,900,832 | Prime |
85 | 43*29596983-1 | 28 February 2022 | 2,888,982 | Prime |
86 | 121*29584444+1 | 20 November 2020 | 2,885,208 | Prime |
87 | 11*29381365+1 | 7 March 2020 | 2,824,074 | Prime |
88 | 27653×29167433 + 1 | 8 June 2005 | 2,759,677 | Prime |
89 | 90527×29162167 + 1 | 30 June 2010 | 2,758,093 | Prime |
- | 29092392 + 40291 | February 2011 | 2,737,083 | PRP |
90 | 6795×29144320 - 1 | 31 March 2021 | 2,752,719 | Prime |
91 | 1323365*1161323365+1 | 18 January 2018 | 2,732,038 | Prime |
92 | 13×28989858 + 1 | 10 March 2020 | 2,706,219 | Prime |
93 | 4159×28938471 - 1 | 19 April 2022 | 2,690,752 | Prime |
94 | 273809×28932416 − 1 | 13 December 2017 | 2,688,931 | Prime |
95 | 2×35570081 + 1 | 14 February 2020 | 2,657,605 | Prime |
96 | 25×28788628 + 1 | 1 March 2021 | 2,645,643 | Prime |
97 | 2038×3661028507 − 1 | 4 April 2016 | 2,636,562 | Prime |
98 | 17×28636199 + 1 | 17 February 2021 | 2,599,757 | Prime |
99 | 75898524288 + 1 | 19 November 2021 | 2,558,647 | Prime |
100 | 25×28456828 + 1 | 28 January 2021 | 2,545,761 | Prime |
101 | 39×28413422 + 1 | 23 January 2021 | 2,532,694 | Prime |
102 | 31×28348000 + 1 | 19 January 2021 | 2,513,000 | Prime |
103 | 27×28342438 - 1 | 1 February 2021 | 2,511,326 | Prime |
104 | 3867×28261084 - 1 | 14 April 2021 | 2,486,838 | Prime |
- | August 2020 | 2,449,236 | PRP | |
105 | 273662×53493296 - 1 | 7 December 2021 | 2,441,715 | Prime |
106 | 11×28103463 + 1 | 6 March 2020 | 2,439,387 | Prime |
107 | 102818×53440382 - 1 | 8 October 2021 | 2,404,729 | Prime |
108 | 11×27971110 - 1 | 25 November 2019 | 2,399,545 | Prime |
109 | 27×27963247 + 1 | 16 January 2021 | 2,397,178 | Prime |
110 | 3177×27954621 - 1 | 13 June 2021 | 2,394,584 | Prime |
111 | 39×27946769 + 1 | 15 January 2021 | 2,392,218 | Prime |
112 | 7×63072198 + 1 | 4 August 2019 | 2,390,636 | Prime |
113 | 3765×27904593 - 1 | 10 January 2021 | 2,379,524 | Prime |
114 | 29×27899985 + 1 | 15 January 2021 | 2,378,134 | Prime |
115 | 861×27895451 - 1 | 21 February 2021 | 2,376,771 | Prime |
- | July 2021 | 2,358,349 | PRP | |
116 | 28433×27830457 + 1 | 31 December 2004 | 2,357,207 | Prime |
117 | 5×27755002 - 1 | 23 September 2021 | 2,334,489 | Prime |
118 | 2545×27732265 - 1 | 13 January 2021 | 2,327,648 | Prime |
119 | 5539×27730709 - 1 | 15 January 2021 | 2,327,180 | Prime |
120 | 4817×27719584 - 1 | 13 June 2021 | 2,323,831 | Prime |
121 | 1341174×531341174 + 1 | 22 August 2017 | 2,312,561 | Prime |
122 | 9467×27680034 - 1 | 20 February 2022 | 2,311,925 | Prime |
- | February 2022 | 2,307,015 | PRP | |
123 | 45×27661004 + 1 | 13 December 2020 | 2,306,194 | Prime |
124 | 15×27619838 + 1 | 24 December 2020 | 2,293,801 | Prime |
125 | 3597×27580693 - 1 | 10 January 2021 | 2,282,020 | Prime |
126 | 7401×27523295 - 1 | 21 February 2021 | 2,264,742 | Prime |
127 | 45×27513661 + 1 | 12 November 2020 | 2,261,839 | Prime |
128 | 11 January 2017 | 2,259,865 | Prime | |
129 | 29×27374577 + 1 | 28 October 2020 | 2,219,971 | Prime |
130 | 109838×53168862 - 1 | 13 August 2020 | 2,219,971 | Prime |
131 | 101×27345194 - 1 | 5 October 2019 | 2,219,971 | Prime |
- | March 2018 | 2,201,714 | PRP | |
132 | 15×27300254 + 1 | 25 October 2020 | 2,219,971 | Prime |
133 | 422429! + 1 | 21 February 2022 | 2,193,027 | Prime |
134 | 1759×27284439 - 1 | 28 August 2021 | 2,192,838 | Prime |
135 | 737×27269322 − 1 | 10 August 2017 | 2,188,287 | Prime |
136 | 118568×53112069 + 1 | 2 May 2020 | 2,175,248 | Prime |
137 | 6039×27207973 − 1 | 24 March 2021 | 2,169,820 | Prime |
138 | 502573×27181987 − 1 | 4 October 2014 | 2,162,000 | Prime |
139 | 402539×27173024 − 1 | 2 October 2014 | 2,159,301 | Prime |
140 | 3343×27166019 - 1 | 29 September 2016 | 2,157,191 | Prime |
141 | 161041×27107964 + 1 | 8 January 2015 | 2,139,716 | Prime |
- | October 2017 | 2,131,318 | PRP | |
142 | 27*27046834+1 | 16 October 2018 | 2,121,310 | Prime |
143 | 1759×27046791 - 1 | 28 August 2021 | 2,121,299 | Prime |
144 | 327×27044001 - 1 | 13 January 2021 | 2,120,459 | Prime |
145 | 5×27037188 - 1 | 22 September 2021 | 2,118,406 | Prime |
146 | 3×27033641 + 1 | 21 February 2011 | 2,117,338 | Prime |
147 | 33661×27031232 + 1 | 30 October 2007 | 2,116,617 | Prime |
148 | 6 January 2017 | 2,114,016 | Prime | |
149 | 207494*53017502-1 | 19 March 2020 | 2,109,149 | Prime |
150 | 15*26993631-1 | 25 August 2021 | 2,105,294 | Prime |
151 | 8943501*26972593-1 | 8 January 2022 | 2,098,967 | Prime |
152 | 26972593 – 1 | 1 June 1999 | 2,098,960 | Prime |
153 | 6219*26958945-1 | 7 January 2021 | 2,094,855 | Prime |
154 | 51*26945567+1 | 26 May 2020 | 2,090,826 | Prime |
155 | 238694*52979422-1 | 13 March 2020 | 2,082,532 | Prime |
156 | 4×721119849 − 1 | 7 September 2016 | 2,079,933 | Prime |
157 | 33*26894190-1 | 27 July 2021 | 2,075,360 | Prime |
158 | 2345*26882320-1 | 13 April 2022 | 2,071,789 | Prime |
159 | 146264*52953282-1 | 10 March 2020 | 2,064,261 | Prime |
160 | 69*26838971-1 | 1 March 2020 | 2,058,738 | Prime |
161 | 35816*52945294-1 | 5 March 2020 | 2,058,677 | Prime |
162 | 127*26836153-1 | 25 June 2018 | 2,057,890 | Prime |
163 | 19*26833086+1 | 25 October 2020 | 2,056,966 | Prime |
164 | 40597×26808509 – 1 | 27 November 2013 | 2,049,571 | Prime |
165 | 283*26804701-1 | 19 January 2020 | 2,048,431 | Prime |
166 | 1861209*26789999+1 | 2 December 2020 | 2,044,000 | Prime |
167 | 5817*26789459-1 | 9 January 2021 | 2,043,835 | Prime |
168 | 8435*26786180-1 | 7 January 2021 | 2,042,848 | Prime |
169 | 51*26753404+1 | 26 May 2020 | 2,032,979 | Prime |
170 | 9995*26711008-1 | 31 December 2020 | 2,020,219 | Prime |
171 | 39*26684941+1 | 20 October 2020 | 2,012,370 | Prime |
172 | 6679881×26679881 + 1 | 25 July 2009 | 2,010,852 | Prime |
173 | 37×26660841 − 1 | 30 July 2014 | 2,005,115 | Prime |
174 | 39*26648997+1 | 20 October 2020 | 2,001,550 | Prime |
References
- Chris Caldwell, The Prime Glossary: megaprime at The PrimePages. Retrieved on 2008-01-04.
- "Chris Caldwell, The Largest Known Prime by Year: A Brief History". Archived from the original on 2016-01-01. Retrieved 2008-01-04.
{{cite web}}
: CS1 maint: bot: original URL status unknown (link) - Chris Caldwell, The Largest Known Primes at The PrimePages.
- Henri Lifchitz & Renaud Lifchitz, Probable Primes Top 10000, primenumbers.net
- GIMPS press release, GIMPS Finds First Million-Digit Prime. Retrieved on 2008-01-04.
- Chris Caldwell, The Largest Known Prime by Year: A Brief History at The PrimePages. Retrieved on 2008-09-28.
- Patrick De Geest, 10^999999 + y, World!Of Numbers
- Caldwell, Chris K. "THE LARGEST KNOWN PRIMES (The 5,000 largest known primes)". Retrieved 23 November 2018.
- "Official press release of 51st Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 7 December 2018.
- "Official press release of 50th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 26 December 2017.
- "Official press release of 49th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 7 January 2016.
- "Official press release of 48th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- "Official press release of 45th and 46th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 10 September 2008.
- "Official press release of 47th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- "Official press release of 44th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- Official announcement of discovery of 10223×231172165 + 1, PrimeGrid
- "Official press release of 43rd Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- "Official press release of 42nd Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- "Official press release of 41st Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- Official announcement of discovery of 202705×221320516 + 1, PrimeGrid
- "Official press release of 40th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- Official announcement of discovery of 10590941048576 + 1, PrimeGrid
- Official announcement of discovery of 9194441048576 + 1, PrimeGrid
- Official announcement of discovery of 168451×219375200 + 1, PrimeGrid
- Official announcement of discovery of 3×217748034 - 1, PrimeGrid
- Official announcement of discovery of 8508301×217016603-1, PrimeGrid
- Official announcement of discovery of 3×216819291-1, PrimeGrid
- Official announcement of discovery of 3×216408818+1, PrimeGrid
- Official announcement of discovery of 99739×214019102-1, PrimeGrid
- "Official press release of 39th Mersenne prime number". Great Internet Mersenne Prime Search. Retrieved 25 January 2013.
- Official announcement of discovery of 2805222×55610444 + 1, PrimeGrid
- Official announcement of discovery of 3×211731850 − 1, PrimeGrid
- Official announcement of discovery of 3×211484018 − 1, PrimeGrid
- Official announcement of discovery of 3×210829346 + 1, PrimeGrid
- Official announcement of discovery of 475856524288 + 1, PrimeGrid
- Official announcement of discovery of 356926524288 + 1, PrimeGrid
- Official announcement of discovery of 341112524288 + 1, PrimeGrid
- Generalized Sierpinski/Riesel primes
- Official announcement of discovery of 75898524288 + 1, PrimeGrid
- Official announcement of discovery of 273662*53493296 + 1, PrimeGrid
- 102818*53440382-1, PrimeGrid
- Official announcement of discovery of 502573×27181987 − 1, PrimeGrid
- Official announcement of discovery of 402539×27173024 − 1, PrimeGrid
- Official announcement of discovery of 3×27033641 + 1, PrimeGrid
- Official announcement of discovery of 40597×26808509 – 1, PrimeGrid
- Official announcement of discovery of 6679881×26679881 + 1, PrimeGrid
External links
- Chris Caldwell, The Largest Known Primes Database at The PrimePages
- Top PRPs
- A text file for the top primes
- PrimeGrid’s 321 Prime Search, about the discovery of 3×26090515−1