428 221 Exponent Status

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

PrimeNet Exponent Status

M_n

Status

Details

Factored

Factor	Digits	Bits	Date
270237906288780283755651875647	30	97.8	2019-05-09 23:21:38

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	295 / 640

Estimated T-Level: 27.3 ⓘ

TF below 2^86 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Shift
Verified (Factored)		David Slowinski	2AE2	0
Verified (Factored)		Jay R. Hill	254DA06841256AE2	0
Verified (Factored)		Eivind Triel	254DA06841256AE2	34099
Verified (Factored)		Albrecht Heeffer	254DA06841256AE2	77118
Verified (Factored)		Bryan Fullerton	254DA06841256AE2	270134

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified	2019-05-10	Niels_Mache_Nextcloud	FEC673209E33168B	1	217893	5	3
Verified	2019-05-10	Daniil Tsarkov	FEC673209E33168B	1	17504	5	3

History

Date	User	Type	Result
2019-05-10	Daniil Tsarkov	C-PRP	M428221/270237906288780283755651875647 : FEC673209E33168B PRP: Verified PRP without proof (small exponent)
2019-05-10	Niels_Mache_Nextcloud	C-PRP	M428221/270237906288780283755651875647 : FEC673209E33168B PRP: Verified PRP without proof (small exponent)
2019-05-09	alex	F-ECM	Factor: 270237906288780283755651875647 / (ECM curve 182, B1=250000, B2=25000000, Sigma=6735534339562310)
2018-12-11	Gordon Spence	NF	no factor from 2^65 to 2^66
2017-12-21	Gordon Spence	NF	no factor from 2^64 to 2^65
2016-02-23	Mark Rose	NF	no factor from 2^58 to 2^60
2015-11-16	Gordon Spence	NF	no factor from 2^63 to 2^64
2015-11-16	Gordon Spence	NF	no factor from 2^62 to 2^63
2013-01-07	markr	NF-PM1	B1=25000000, B2=1000000000, E=12
2012-12-01	dbaugh	NF	no factor from 2^61 to 2^62
2012-11-27	dbaugh	NF	no factor from 2^60 to 2^61
2012-05-29	Joss	NF-PM1	B1=2993164
2010-08-05	Rob_Dee	NF-PM1	B1=1000000, B2=2000000, E=6
2010-08-04	Rob_Dee	NF-PM1	B1=500000, B2=1000000