12 641 Exponent Status

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

PrimeNet Exponent Status

M_n

Details

Composite, with 5 known prime factors. Cofactor is composite.

Trial Factored to 2⁶⁸

TF target 2⁴⁴

Factored

Factor	Digits	Bits	Date
783743	6	19.6	old
4045121	7	21.9	2008-08-26 19:58:37
18198590369	11	34.1	2008-08-26 19:58:37
41249479151	11	35.3	2008-08-26 19:58:37
234221764576478857	18	57.7	2008-08-29 02:24:31

P-1 factors

Date	Factors	B1	B2
2023-05-13	No new factors discovered	100000000000	120417199046794656

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	640 / 640
35	1000000	1566 / 1566
40	3000000	4588 / 4588
45	11000000	1463 / 9201

Estimated T-Level: 40.8 ⓘ

TF below 2^131 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	55CD52A60DF88A20	5	0	1	3
Verified	No proof (small exponent)	2017-10-02	kkmrkkblmbrbk	55CD52A60DF88A20	5	0	1	3
Verified	No proof (small exponent)	2017-12-07	ATH	55CD52A60DF88A20	5	5860	1	3
Verified	No proof (small exponent)	2020-04-17	Oliver Kruse	82A8F5FC60704077	5	8993	5	3
Verified	No proof (small exponent)	2024-07-01	kkmrkkblmbrbk	82A8F5FC60704077	5	1956	5	3

History

Date	User	Type	Result
2025-03-12	masser	NF-PP1	Start=122/17, B1=430000000, B2=429570000000
2025-02-18	masser	NF-PP1	Start=6/5, B1=430000000, B2=429570000000
2025-01-17	masser	NF-PP1	Start=2/7, B1=430000000, B2=429570000000
2024-07-01	kkmrkkblmbrbk	C-PRP	M12641/18198590369/234221764576478857/4045121/41249479151/783743 : 82A8F5FC60704077
2023-05-13	Anton Repko	F-PM1	Factor: 234221764576478857 / B1=100000000000, B2=120417199046794650
2021-08-27	Seth_Tr	NF-PM1	B1=400000000
2020-04-17	Oliver Kruse	C-PRP	M12641/783743/4045121/18198590369/41249479151/234221764576478857 : 82A8F5FC60704077
2017-12-07	ATH	C-PRP	M12641/783743/4045121/18198590369/41249479151/234221764576478857 : 55CD52A60DF88A20
2017-10-02	kkmrkkblmbrbk	C-PRP	M12641/783743/4045121/18198590369/41249479151/234221764576478857 : 55CD52A60DF88A20
2017-09-21	Oliver Kruse	C-PRP	M12641/783743/4045121/18198590369/41249479151/234221764576478857 : 55CD52A60DF88A20
2008-08-29	-anonymous-	F-ECM	Factor: 234221764576478857
2008-08-26	-anonymous-	F	Factor: 41249479151
2008-08-26	-anonymous-	F	Factor: 18198590369
2008-08-26	-anonymous-	F	Factor: 4045121