1 619 887 Exponent Status

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

PrimeNet Exponent Status

M_n

Status

Details

Composite, with 3 known prime factors. Cofactor is composite.

Factored

Factor	Digits	Bits	Date
220304633	9	27.7	old
6667999174033	13	42.6	2008-07-15 07:44:26
4246219962011470330218201511	28	91.8	2022-10-18 10:22:47

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	9488D49F5B5DA38E	0	1	3

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified (Factored)	2017-10-02	Oliver Kruse	EE36E90CBA431E19	2	0	1	3
Verified (Factored)	2017-11-01	kkmrkkblmbrbk	EE36E90CBA431E19	2	848722	1	3
Verified	2022-10-18	Kevin_9611	9488D49F5B5DA38E	3	262672	5	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	9488D49F5B5DA38E PRP proof power = 6 PRP: Verified (Factored) Proof certified good
2022-10-18	Chad Steenerson	CERT	PRP Certification Proof certified good
2022-10-18	Kevin_9611	C-PRP	M1619887/220304633/6667999174033/4246219962011470330218201511 : 9488D49F5B5DA38E PRP proof power = 6 PRP: Verified Proof certified good
2022-10-18	TJAOI	F-ECM	Factor: 4246219962011470330218201511 / (ECM curve 23, B1=250000, B2=40000000)
2017-11-01	kkmrkkblmbrbk	C-PRP	M1619887/220304633/6667999174033 : EE36E90CBA431E19 PRP: Verified (Factored) PRP without proof (not generated)
2017-10-02	Oliver Kruse	C-PRP	M1619887/220304633/6667999174033 : EE36E90CBA431E19 PRP: Verified (Factored) PRP without proof (not generated)
2016-03-17	alpertron	NF-PM1	B1=500000, B2=15000000, E=12
2008-07-15	J Feitsma	F	Factor: 6667999174033