81 528 037 Exponent Status

Great Internet Mersenne Prime Search
GIMPS
Finding World Record Primes Since 1996

PrimeNet Exponent Status

M_n

Details

Composite: proven not-prime with Lucas-Lehmer test

No factors below 2⁷⁶

TF target 2⁷⁵

P-1

B1 =	695000
B2 =	14247500

Status	Date	User	Residue	Shift	Software
Verified	2017-10-23	GerardCBlais	CE858DC64DE83D7B	75651769	Windows 64-bit,Prime95,v28.5,build 2
Verified	2026-04-07	KIM	CE858DC64DE83D7B	46004964	Windows 64-bit,Prime95,v30.19,build 20

History

Date	User	Type	Result
2026-04-07	KIM	C-LL	CE858DC64DE83D7B
2025-10-05	Sid & Andy	NF	no factor TF: 75-76
2017-10-23	GerardCBlais	C-LL	CE858DC64DE83D7B
2016-10-09	TheJudger	NF-PM1	B1=695000, B2=14247500, E=12
2016-09-20	AirSquirrels	NF	no factor TF: 74-75
2016-09-20	AirSquirrels	NF	no factor TF: 73-74
2016-09-20	AirSquirrels	NF	no factor TF: 72-73
2016-09-20	AirSquirrels	NF	no factor TF: 71-72
2011-02-26	steinrar	NF	no factor TF: 70-71
2011-02-26	steinrar	NF	no factor TF: 69-70
2011-02-26	steinrar	NF	no factor TF: 68-69
2011-02-26	steinrar	NF	no factor TF: 67-68
2011-02-26	steinrar	NF	no factor TF: 65-67
2010-12-13	Architects Cubed	NF	no factor TF: 64-65