20 825 591 Exponent Status

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

PrimeNet Exponent Status

M_n

Status

Details

Composite: proven not-prime with Lucas-Lehmer test

TF

No factors below 2⁷⁴

TF target 2⁶⁹

P-1

B1 =	3500000
B2 =	255500000

Status	Date	User	Residue	Shift
Verified	2007-04-23	Ars Technica Team Prime Rib	D328A6060FD5B02A	2707461
Verified	2008-05-11	Ing. Pavel PaJaSoft Janousek	D328A6060FD5B02A	1632072

History

Date	User	Type	Result
2021-12-16	-Anonymous-	NF	no factor from 2^73 to 2^74
2021-11-12	-Anonymous-	NF	no factor from 2^72 to 2^73
2021-01-25	gLauss	NF-PM1	B1=3500000, B2=255500000
2021-01-24	gLauss	NF	no factor from 2^71 to 2^72
2021-01-24	gLauss	NF	no factor from 2^70 to 2^71
2018-05-25	ramgeis	NF	no factor from 2^69 to 2^70
2017-10-08	VictordeHollander	NF	no factor from 2^68 to 2^69
2017-04-25	ramgeis	NF	no factor from 2^67 to 2^68
2015-03-29	NR	NF	no factor from 2^66 to 2^67