2 208 061 Exponent Status

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

PrimeNet Exponent Status

M_n

Status

Details

Factored

Factor	Digits	Bits	Date
41873414731607178709820449	26	85.1	2015-11-11 05:09:37

ECM

Digits	B1	Curves
25	50000	121 / 280

Estimated T-Level: 22.2 ⓘ

TF below 2^69 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Shift
Verified (Factored)	1998-03-31	Bruce Mitchell	ABC2C4316CC76A4A	0
Verified (Factored)	1999-03-01	Kent Lee	ABC2C4316CC76A4A	1412377

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified	2017-09-30	alpertron	19D7C5BBFF5A10DD	1	0	1	3
Verified	2017-10-25	Oliver Kruse	19D7C5BBFF5A10DD	1	990348	1	3

P-1 factors

Date	Factor	B1	B2
2015-11-11	41873414731607178709820449	1000000	2500000

History

Date	User	Type	Result
2017-10-25	Oliver Kruse	C-PRP	M2208061/41873414731607178709820449 : 19D7C5BBFF5A10DD PRP: Verified PRP without proof (not generated)
2017-09-30	alpertron	C-PRP	M2208061/41873414731607178709820449 : 19D7C5BBFF5A10DD PRP: Verified PRP without proof (not generated)
2016-04-15	alpertron	NF-PM1	B1=500000, B2=15000000, E=12
2015-11-11	Alexander Dubrovin	F-PM1	Factor: 41873414731607178709820449 / (P-1, B1=1000000, B2=2500000, E=6)
2015-10-21	ramgeis	NF	no factor from 2^65 to 2^66
2015-03-06	VictordeHollander	NF	no factor from 2^64 to 2^65
2015-03-06	VictordeHollander	NF	no factor from 2^63 to 2^64
2013-12-04	LaurV	NF	no factor from 2^62 to 2^63
2012-01-07	Squeeky_Squirrel	NF-PM1	B1=135000, B2=2733750, E=6
2011-01-16	Joss	NF-PM1	B1=50000
2009-01-07	Sturle Sunde	NF	no factor from 2^61 to 2^62
2009-01-02	Sturle Sunde	NF	no factor from 2^60 to 2^61