12 901 981 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 2⁷³

TF target 2⁶⁸

P-1

B1 =	600000
B2 =	620747400

ECM

Digits	B1	Curves
25	50000	2 / 280

Estimated T-Level: 20.0 ⓘ

Status	Date	User	Residue	Shift
Verified	2001-11-24	Goede Schueler/Christoph Steinbeck	C8FE29DDB3A01656	7426492
Verified	2005-09-03	Daniel Swanson	C8FE29DDB3A01656	10582315

History

Date	User	Type	Result
2021-12-24	Luminescence	NF-PM1	B1=600000, B2=620747400
2021-11-23	lycorn	NF	no factor from 2^72 to 2^73
2021-10-29	-Anonymous-	NF	no factor from 2^71 to 2^72
2021-08-30	SRBase	NF	no factor from 2^70 to 2^71
2021-08-07	SRBase	NF	no factor from 2^69 to 2^70
2018-01-07	ramgeis	NF	no factor from 2^68 to 2^69
2018-01-07	ramgeis	NF	no factor from 2^67 to 2^68
2015-07-02	Tha	NF-PM1	B1=300000, B2=6000000, E=6
2015-04-13	Tha	NF	no factor from 2^66 to 2^67
2014-05-12	Nesowa	NF	no factor from 2^65 to 2^66
2013-06-01	lycorn	NF	no factor from 2^64 to 2^65