15 936 521 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 =	4096000
B2 =	18145447320

ECM

Digits	B1	Curves
25	50000	1 / 280

Estimated T-Level: 20.0 ⓘ

Status	Date	User	Residue	Shift
Verified	2003-01-09	Johannes Stahl	123361211EBF6D7A	9927723
Verified	2006-09-04	Phil Nelson	123361211EBF6D7A	6939340

History

Date	User	Type	Result
2025-01-11	Jason Lynch	NF-PM1	B1=4096000, B2=18145447320
2022-02-18	-Anonymous-	NF	no factor from 2^73 to 2^74
2022-02-18	-Anonymous-	NF	no factor from 2^72 to 2^73
2021-09-21	-Anonymous-	NF	no factor from 2^71 to 2^72
2021-09-05	lycorn	NF	no factor from 2^70 to 2^71
2021-05-13	lycorn	NF	no factor from 2^69 to 2^70
2020-12-26	Tha	NF-PM1	B1=1500000, B2=30000000, E=12
2018-03-03	ramgeis	NF	no factor from 2^68 to 2^69
2018-03-03	ramgeis	NF	no factor from 2^67 to 2^68
2016-03-16	Mark Rose	NF	no factor from 2^65 to 2^66
2014-07-29	Nesowa	NF	no factor from 2^66 to 2^67