2 121 631 Exponent Status

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GIMPS
Finding World Record Primes Since 1996

PrimeNet Exponent Status

M_n

Status

Details

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

Factored

Factor	Digits	Bits	Date
123054599	9	26.9	old
280055292001	12	38.0	2008-07-14 20:20:36
45028778013048738142439	23	75.3	2022-09-06 16:50:23
97039556231293194800129	23	76.4	2016-03-09 11:18:44
89605272640837289319020329	26	86.2	2024-11-12 10:05:54

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	166 / 640

Estimated T-Level: 26.3 ⓘ

TF below 2^82 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified (Factored)	2017-10-07	Oliver Kruse	81FB7E9E9DC3B564	1	0	1	3
Verified (Factored)	2017-10-17	Oliver Kruse	C0C498122148A3B3	3	665280	5	3
Verified (Factored)	2017-11-17	ATH	C0C498122148A3B3	3	1274503	5	3
Verified (Factored)	2022-09-09	_p95holder_	C0C498122148A3B3	4	794994	5	3
Verified	2024-11-12	Naegi Makoto	C0C498122148A3B3	5	614056	5	3

P-1 factors

Date	Factor	B1	B2
2016-03-09	97039556231293194800129	500000	15000000

History

Date	User	Type	Result
2024-11-12	Theo Polidano	CERT	PRP Certification Proof certified good
2024-11-12	Naegi Makoto	C-PRP	M2121631/123054599/280055292001/97039556231293194800129/45028778013048738142439/89605272640837289319020329 : C0C498122148A3B3 PRP proof power = 7 PRP: Verified Proof certified good
2024-11-12	TJAOI	F-ECM	Factor: 89605272640837289319020329 / (ECM curve 27, B1=250000, B2=264647565, Edwards Sigma=5932614518455434)
2022-09-09	_p95holder_	C-PRP	M2121631/123054599/280055292001/97039556231293194800129/45028778013048738142439 : C0C498122148A3B3 PRP: Verified (Factored) PRP without proof (not generated)
2022-09-06	_p95holder_	F-ECM	Factor: 45028778013048738142439 / (ECM curve 5, B1=50000, B2=5000000)
2017-11-17	ATH	C-PRP	M2121631/123054599/280055292001/97039556231293194800129 : C0C498122148A3B3 PRP: Verified (Factored) PRP without proof (not generated)
2017-10-17	Oliver Kruse	C-PRP	M2121631/123054599/280055292001/97039556231293194800129 : C0C498122148A3B3 PRP: Verified (Factored) PRP without proof (not generated)
2017-10-07	Oliver Kruse	C-PRP	M2121631/123054599/280055292001/97039556231293194800129 : 81FB7E9E9DC3B564 PRP: Verified (Factored) PRP without proof (not generated)
2016-03-09	alpertron	F-PM1	Factor: 97039556231293194800129 / (P-1, B1=500000, B2=15000000, E=12)
2008-07-14	George Woltman	F-ECM	Factor: 280055292001