13 487 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
107897	6	16.7	old
71896820465147337866380177	26	85.9	2008-10-25 20:59:11

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	640 / 640
35	1000000	1566 / 1566
40	3000000	4588 / 4588
45	11000000	1528 / 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	3C6BE5B33C7DBC8B	2	0	1	3
Verified	No proof (small exponent)	2017-10-12	kkmrkkblmbrbk	3C6BE5B33C7DBC8B	2	7460	1	3
Verified	No proof (small exponent)	2020-04-17	Oliver Kruse	57F7FBD2EA005565	2	9792	5	3
Verified	No proof (small exponent)	2024-07-01	kkmrkkblmbrbk	57F7FBD2EA005565	2	10684	5	3

History

Date	User	Type	Result
2025-02-25	masser	NF-PP1	Start=143/31, B1=430000000, B2=429570000000
2025-02-11	masser	NF-PP1	Start=2/7, B1=430000000, B2=429570000000
2025-01-26	masser	NF-PP1	Start=6/5, B1=430000000, B2=429570000000
2024-07-01	kkmrkkblmbrbk	C-PRP	M13487/107897/71896820465147337866380177 : 57F7FBD2EA005565
2024-01-29	-anonymous-	NF-PM1	B1=100000000000, B2=122154521813133810
2023-05-19	JacobZ	NF-PM1	B1=8100000000, B2=31521845619113850
2022-02-05	Joss	NF-PM1	B1=1000000, B2=2389799412000
2020-04-17	Oliver Kruse	C-PRP	M13487/107897/71896820465147337866380177 : 57F7FBD2EA005565
2017-10-12	kkmrkkblmbrbk	C-PRP	M13487/107897/71896820465147337866380177 : 3C6BE5B33C7DBC8B
2017-09-21	Oliver Kruse	C-PRP	M13487/107897/71896820465147337866380177 : 3C6BE5B33C7DBC8B
2017-09-21	Oliver Kruse	C-PRP	M13487/107897/71896820465147337866380177 : 3C6BE5B33C7DBC8B
2008-10-25	Will Edgington	F-ECM	Factor: 71896820465147337866380177