11 491 Exponent Status

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

PrimeNet Exponent Status

M_n

Details

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

Trial Factored to 2⁶⁸

TF target 2⁴⁴

Factored

Factor	Digits	Bits	Date
7646938753	10	32.8	old
575865804591108063324617025817	30	98.9	2015-08-15 09:09:16

P-1 factors

Date	Factors	B1	B2
2023-01-20	No new factors discovered	100000000000	122192573512709696

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	640 / 640
35	1000000	1566 / 1566
40	3000000	4588 / 4588
45	11000000	2598 / 9201

Estimated T-Level: 41.4 ⓘ

TF below 2^133 is very unlikely to find new factors due to ECM effort.

Status	Proof	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified	No proof (small exponent)	2017-09-21	Oliver Kruse	91D64F2AFB254626	2	0	1	3
Verified	No proof (small exponent)	2017-10-02	kkmrkkblmbrbk	91D64F2AFB254626	2	0	1	3
Verified	No proof (small exponent)	2017-12-07	ATH	91D64F2AFB254626	2	7068	1	3
Verified	No proof (small exponent)	2020-04-17	Oliver Kruse	1CB804D8FBF8682E	2	3942	5	3
Verified	No proof (small exponent)	2024-07-01	kkmrkkblmbrbk	1CB804D8FBF8682E	2	8787	5	3

History

Date	User	Type	Result
2025-03-15	masser	NF-PP1	Start=143/13, B1=430000000, B2=429570000000
2025-03-01	masser	NF-PP1	Start=6/5, B1=430000000, B2=429570000000
2025-01-23	masser	NF-PP1	Start=2/7, B1=430000000, B2=429570000000
2024-07-01	kkmrkkblmbrbk	C-PRP	M11491/575865804591108063324617025817/7646938753 : 1CB804D8FBF8682E
2023-01-20	-anonymous-	F-PM1	Factor: 575865804591108063324617025817 / B1=100000000000, B2=122192573512709700
2020-04-17	Oliver Kruse	C-PRP	M11491/7646938753/575865804591108063324617025817 : 1CB804D8FBF8682E
2017-12-07	ATH	C-PRP	M11491/7646938753/575865804591108063324617025817 : 91D64F2AFB254626
2017-10-02	kkmrkkblmbrbk	C-PRP	M11491/7646938753/575865804591108063324617025817 : 91D64F2AFB254626
2017-09-21	Oliver Kruse	C-PRP	M11491/7646938753/575865804591108063324617025817 : 91D64F2AFB254626
2016-09-07	kkmrkkblmbrbk	NF-PM1	B1=100000000, B2=10000000000, E=12
2015-08-15	BloodIce	F-ECM	Factor: 575865804591108063324617025817