8 263 Exponent Status

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

PrimeNet Exponent Status

M_n

Status

Details

Composite, with 1 known prime factor. Cofactor is composite.

Factored

Factor	Digits	Bits	Date
163604664259317708257	21	67.1	old

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	640 / 640
35	1000000	1566 / 1566
40	3000000	4588 / 4588
45	11000000	9201 / 9201
50	44000000	6889 / 16550

Estimated T-Level: 47.1 ⓘ

TF below 2^151 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified	2017-09-21	Oliver Kruse	F12B86BF6B06571F	1	0	1	3
Verified	2017-10-12	kkmrkkblmbrbk	F12B86BF6B06571F	1	4598	1	3
Verified	2020-04-17	Oliver Kruse	E448390EA45F5096	1	7191	5	3
Verified	2024-07-01	kkmrkkblmbrbk	E448390EA45F5096	1	5251	5	3

History

Date	User	Type	Result
2024-07-01	kkmrkkblmbrbk	C-PRP	M8263/163604664259317708257 : E448390EA45F5096 PRP: Verified PRP without proof (small exponent)
2023-08-30	JacobZ	NF-PM1	B1=71000000000, B2=265422648792401100
2021-12-16	Lisander Viaene	NF-PM1	B1=100000000
2020-04-17	Oliver Kruse	C-PRP	M8263/163604664259317708257 : E448390EA45F5096 PRP: Verified PRP without proof (small exponent)
2017-10-12	kkmrkkblmbrbk	C-PRP	M8263/163604664259317708257 : F12B86BF6B06571F PRP: Verified PRP without proof (not generated)
2017-09-21	Oliver Kruse	C-PRP	M8263/163604664259317708257 : F12B86BF6B06571F PRP: Verified PRP without proof (not generated)
2017-09-21	Oliver Kruse	C-PRP	M8263/163604664259317708257 : F12B86BF6B06571F PRP without proof (not generated)