1 626 073 Exponent Status

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

PrimeNet Exponent Status

M_n

Status

Details

Composite, with 2 known prime factors. Cofactor is composite.

Factored

Factor	Digits	Bits	Date
28927838671	11	34.8	old
525187560121895761	18	58.9	2015-05-02 17:25:47

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	134 / 640

Estimated T-Level: 26.0 ⓘ

TF below 2^82 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Shift	Type	Base
Verified (Factored)	2025-09-02	Kriesel	A62B5A7D3AFE1687	0	1	3

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified	2017-10-02	Oliver Kruse	1C44B7C4B843E583	2	0	1	3
Verified	2017-11-01	kkmrkkblmbrbk	1C44B7C4B843E583	2	526787	1	3

P-1 factors

Date	Factor	B1	B2
2015-05-02	525187560121895761	500000	15000000

History

Date	User	Type	Result
2025-09-03	Carlos Pinho	CERT	PRP Certification CERT proof power = 6 Proof certified good
2025-09-02	Kriesel	C-PRP	A62B5A7D3AFE1687 PRP proof power = 6 PRP: Verified (Factored) Proof certified good
2017-11-01	kkmrkkblmbrbk	C-PRP	M1626073/28927838671/525187560121895761 : 1C44B7C4B843E583 PRP: Verified PRP without proof (not generated)
2017-10-02	Oliver Kruse	C-PRP	M1626073/28927838671/525187560121895761 : 1C44B7C4B843E583 PRP: Verified PRP without proof (not generated)
2015-05-02	alpertron	F-PM1	Factor: 525187560121895761 / (P-1, B1=500000, B2=15000000, E=12)