12 671 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
25343	5	14.6	old
99847481	8	26.6	2008-08-26 19:58:38

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	A5F2512455D601B3	2	0	1	3
Verified	No proof (small exponent)	2017-10-12	kkmrkkblmbrbk	A5F2512455D601B3	2	9790	1	3
Verified	No proof (small exponent)	2020-04-17	Oliver Kruse	4B6584BA29DC97E5	2	11248	5	3
Factored	No proof (small exponent)	2022-05-12	Jorge Coveiro	4B6584BA29DC97E5	1	1997	5	3
Verified	No proof (small exponent)	2024-07-01	kkmrkkblmbrbk	4B6584BA29DC97E5	2	5699	5	3

History

Date	User	Type	Result
2025-03-11	masser	NF-PP1	Start=181/53, 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	M12671/25343/99847481 : 4B6584BA29DC97E5
2023-05-22	-anonymous-	NF-PM1	B1=100000000000, B2=120417199046794650
2022-05-12	Jorge Coveiro	C-PRP	M12671/25343 : 4B6584BA29DC97E5
2020-04-17	Oliver Kruse	C-PRP	M12671/25343/99847481 : 4B6584BA29DC97E5
2017-10-12	kkmrkkblmbrbk	C-PRP	M12671/25343/99847481 : A5F2512455D601B3
2017-09-21	Oliver Kruse	C-PRP	M12671/25343/99847481 : A5F2512455D601B3
2017-09-21	Oliver Kruse	C-PRP	M12671/25343/99847481 : A5F2512455D601B3
2008-08-26	-anonymous-	F	Factor: 99847481