13 381 Exponent Status

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

PrimeNet Exponent Status

M_n

Details

Composite, with 3 known prime factors. Cofactor is composite.

Trial Factored to 2⁶⁸

TF target 2⁴⁴

Factored

Factor	Digits	Bits	Date
49300715543	11	35.5	old
1385046912159998535822293278493773880258517593	46	150.0	2025-08-02 13:36:49
59949415828782946694122869658195559679010800209	47	155.4	2025-08-03 14:50:42

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	640 / 640
35	1000000	1566 / 1566
40	3000000	4588 / 4588
45	11000000	1594 / 9201

Estimated T-Level: 40.9 ⓘ

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
Factored	No proof (small exponent)	2017-09-21	Oliver Kruse	10BE5E1461C66A0B	1	0	1	3
Factored	No proof (small exponent)	2017-10-12	kkmrkkblmbrbk	10BE5E1461C66A0B	1	3023	1	3
Factored	No proof (small exponent)	2020-04-17	Oliver Kruse	FD3CC866A9E9FEFE	1	2731	5	3
Factored	No proof (small exponent)	2024-07-01	kkmrkkblmbrbk	FD3CC866A9E9FEFE	1	9076	5	3
Verified	No proof (small exponent)	2025-08-08	Elysia	FD3CC866A9E9FEFE	3	2512	5	3

History

Date	User	Type	Result
2025-08-08	Elysia	C-PRP	M13381/49300715543/1385046912159998535822293278493773880258517593/59949415828782946694122869658195559679010800209 : FD3CC866A9E9FEFE
2025-08-03	Ryan Propper	F-ECM	Factor: 59949415828782946694122869658195559679010800209
2025-08-02	Ryan Propper	F-ECM	Factor: 1385046912159998535822293278493773880258517593
2025-02-27	masser	NF-PP1	Start=142/61, B1=430000000, B2=429570000000
2025-02-02	masser	NF-PP1	Start=2/7, B1=430000000, B2=429570000000
2025-01-27	masser	NF-PP1	Start=6/5, B1=430000000, B2=429570000000
2024-07-01	kkmrkkblmbrbk	C-PRP	M13381/49300715543 : FD3CC866A9E9FEFE
2023-12-19	-anonymous-	NF-PM1	B1=100000000000, B2=122154521813133810
2023-05-18	JacobZ	NF-PM1	B1=8200000000, B2=35024272926292650
2020-04-17	Oliver Kruse	C-PRP	M13381/49300715543 : FD3CC866A9E9FEFE
2017-10-12	kkmrkkblmbrbk	C-PRP	M13381/49300715543 : 10BE5E1461C66A0B
2017-09-21	Oliver Kruse	C-PRP	M13381/49300715543 : 10BE5E1461C66A0B
2017-09-21	Oliver Kruse	C-PRP	M13381/49300715543 : 10BE5E1461C66A0B