Marin Mersenne 2^P-1
Username
Password
Forgot password?
White
Great Internet Mersenne Prime Search
GIMPS
Finding World Record Primes Since 1996

PrimeNet Exponent Status

Exponent Range:










MnStatusDetails
261431Composite: proven not-prime with Lucas-Lehmer test
TF
No factors below 267
TF target 244
TF below 2^105 is very unlikely to find new factors due to ECM effort.
P-1
B1 = 236900000
B2 = 2729428621920
ECM
DigitsB1Curves
2550000280 / 280
30250000640 / 640
351000000933 / 1566
Estimated T-Level: 33.0 ⓘ
LL
StatusDateUserResidueShift
VerifiedDavid Slowinski4F8A0
VerifiedJohn LyonB35CB0AF50C54F8A0
VerifiedScott FluhrerB35CB0AF50C54F8A0
VerifiedBryan FullertonB35CB0AF50C54F8A102822
VerifiedEivind TrielB35CB0AF50C54F8A122210
VerifiedAlbrecht HeefferB35CB0AF50C54F8A125520
Assigned
AssignedUserWork TypeStage% DoneUpdatedExpired
2025-08-25-Anonymous-factor ECM small0.00 % 2025-08-25
2025-08-22-Anonymous-factor ECM small0.00 % 2025-08-22
History
DateUserTypeResult
2025-04-27tim sNF
no factor from 2^66 to 2^67
2023-02-07masserNF-PP1
Start=6/5, B1=20000000, B2=620000000
2023-01-30masserNF-PP1
Start=78/13, B1=20000000, B2=620000000
2023-01-27masserNF-PP1
Start=2/7, B1=20000000, B2=620000000
2022-12-10Sid & AndyNF-PM1
B1=236900000, B2=2729428621920
2022-03-07LordJuliusNF
no factor from 2^54 to 2^55
2022-02-11lycornNF-PM1
B1=17000000, B2=501736585350
2020-01-02Gordon SpenceNF
no factor from 2^65 to 2^66
2018-03-24BloodERazorNF
no factor from 2^64 to 2^65
2015-12-05Gordon SpenceNF
no factor from 2^63 to 2^64
2015-12-05Gordon SpenceNF
no factor from 2^62 to 2^63
2015-08-25NRNF
no factor from 2^61 to 2^62
2015-02-27David CampeauNF-PM1
B1=17000000, B2=765000000, E=12
2013-10-21David CampeauNF-PM1
B1=2395000, B2=81430000, E=12
2013-07-13lycornNF
no factor from 2^60 to 2^61
2012-02-26JossNF-PM1
B1=2364802
2011-02-11JossNF-PM1
B1=2000000
2009-01-24Sturle SundeNF
no factor from 2^59 to 2^60
2009-01-01Sturle SundeNF
no factor from 2^58 to 2^59