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
28813Composite, with 1 known prime factor. Cofactor is composite.
Factored
FactorDigitsBitsDate
7872623881360425720917968638284867285411341135.92018-03-28 11:15:08
ECM
DigitsB1Curves
2550000280 / 280
30250000640 / 640
3510000001566 / 1566
4030000004588 / 4588
45110000001540 / 9201
Estimated T-Level: 40.8
TF below 2^131 is very unlikely to find new factors due to ECM effort.
LL
StatusDateUserResidueShift
Verified (Factored)Unknown4D010
Verified (Factored)George Woltman009205DF7AABCD010
Verified (Factored)Brian J. Beesley009205DF7AABCD010
Verified (Factored)2015-04-11MadPoo009205DF7AABCD0121270
PRP Cofactor
StatusDateUserResidueNumber of
known factors
ShiftTypeBase
Verified2018-03-28ATH833D4C88AC2D67C51126853
Verified2018-03-28Squeeky_Squirrel833D4C88AC2D67C51663453
History
DateUserTypeResult
2024-11-23masserNF-PP1
Start=6/5, B1=100000000, B2=99900000000
2024-11-22masserNF-PP1
Start=2/7, B1=100000000, B2=99900000000
2024-11-19masserNF-PP1
Start=85/71, B1=100000000, B2=99900000000
2018-03-28Squeeky_SquirrelC-PRP
M28813/78726238813604257209179686382848672854113 : 833D4C88AC2D67C5
PRP: Verified
PRP without proof (small exponent)
2018-03-28ATHC-PRP
M28813/78726238813604257209179686382848672854113 : 833D4C88AC2D67C5
PRP: Verified
PRP without proof (small exponent)
2018-03-28volkiF-ECM
Factor: 78726238813604257209179686382848672854113 / (ECM curve 87, B1=11000000, B2=1100000000)
2017-05-24mikrNF-PM1
B1=12000000000, B2=960000000000, E=12
2016-09-24Sid & AndyNF
no factor from 2^62 to 2^63
2016-02-23LaurVNF
no factor from 2^57 to 2^58
2015-04-11MadPooC-LL
009205DF7AABCD01
2013-11-07David CampeauNF-PM1
B1=204540000, B2=10636080000, E=12
2012-04-02bcp19NF
no factor from 2^61 to 2^62
2012-04-02bcp19NF
no factor from 2^60 to 2^61
2009-02-08Sturle SundeNF
no factor from 2^59 to 2^60
2009-01-15Sturle SundeNF
no factor from 2^58 to 2^59