1 549 921 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
166681604183	12	37.3	old
1755487022231	13	40.7	2008-07-15 10:04:42

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	107 / 640

Estimated T-Level: 25.8 ⓘ

TF below 2^81 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Shift	Type	Base
Verified (Factored)	2025-09-02	Kriesel	99542541F4CF5FBF	0	1	3

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified	2017-10-01	Oliver Kruse	F8B56297F00FC390	2	0	1	3
Verified	2017-10-30	kkmrkkblmbrbk	F8B56297F00FC390	2	370781	1	3

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	99542541F4CF5FBF PRP proof power = 6 PRP: Verified (Factored) Proof certified good
2017-10-30	kkmrkkblmbrbk	C-PRP	M1549921/166681604183/1755487022231 : F8B56297F00FC390 PRP: Verified PRP without proof (not generated)
2017-10-01	Oliver Kruse	C-PRP	M1549921/166681604183/1755487022231 : F8B56297F00FC390 PRP: Verified PRP without proof (not generated)
2016-03-16	alpertron	NF-PM1	B1=500000, B2=15000000, E=12
2008-07-15	J Feitsma	F	Factor: 1755487022231