15 218 153 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
247151197404368795063	21	67.7	2018-01-01 21:55:47

ECM

Digits	B1	Curves
25	50000	1 / 280

Estimated T-Level: 20.0 ⓘ

TF below 2^61 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Shift
Verified (Factored)	2002-05-25	YatHong Yu	B138E918AD720330	9396595
Verified (Factored)	2005-10-04	Carl Riley	B138E918AD720330	392475

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified	2023-07-01	InsolentJaguar	AED393241BFC46DE	1	9213892	5	3

History

Date	User	Type	Result
2023-07-01	Stixxy	CERT	PRP Certification Proof certified good
2023-07-01	InsolentJaguar	C-PRP	M15218153/247151197404368795063 : AED393241BFC46DE PRP proof power = 8 PRP: Verified Proof certified good
2023-05-30	nordi	NF-PM1	B1=400000, B2=407843436
2023-05-14	nordi	NF-PM1	B1=400000
2018-01-01	ramgeis	F	Factor: 247151197404368795063 / TF: 67-68*
2014-05-28	Nesowa	NF	no factor from 2^66 to 2^67
2014-05-28	Nesowa	NF	no factor from 2^65 to 2^66