1 518 973 Exponent Status

PrimeNet Exponent Status

M_n

Status

Details

Composite: proven not-prime with both PRP and Lucas-Lehmer tests

No factors below 2⁶⁸

TF target 2⁶¹

TF below 2^81 is very unlikely to find new factors due to ECM effort.

P-1

B1 =	21700000
B2 =	83431087740

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	104 / 640

Estimated T-Level: 25.8 ⓘ

Status	Date	User	Residue	Shift
Verified		tom ehlert	EE4A1172BB5EAA40	0
Bad	1998-12-13	Yann Forget	396B4D5690FE0B92	1247402
Verified	1999-03-01	Curt Akins	EE4A1172BB5EAA40	1233599
Verified	2015-07-21	MadPoo	EE4A1172BB5EAA40	430186

Status	Date	User	Residue	Shift	Type	Base
Verified	2025-09-01	Kriesel	B39079A75DEC6E3C	0	1	3

History

Date	User	Type	Result
2025-09-03	Carlos Pinho	CERT	PRP Certification CERT proof power = 6 Proof certified good
2025-09-01	Kriesel	C-PRP	B39079A75DEC6E3C PRP proof power = 6 PRP: Verified Proof certified good
2023-09-19	Sid & Andy	NF-PM1	B1=21700000, B2=83431087740
2023-08-15	Joss	NF-PM1	B1=20000000, B2=18510431940
2023-07-02	Joss	NF-PM1	B1=10000000, B2=8716805370
2023-03-08	Joss	NF-PM1	B1=10000000, B2=3990825930
2023-01-12	Joss	NF-PM1	B1=10000000, B2=1627857000
2022-12-22	Joss	NF-PM1	B1=10000000, B2=321015420
2018-06-06	ramgeis	NF	no factor from 2^67 to 2^68
2018-03-12	TJAOI	NF	no factor from 2^66 to 2^67
2016-02-23	Mark Rose	NF	no factor from 2^58 to 2^61
2016-02-23	Mark Rose	NF	no factor from 2^61 to 2^62
2016-02-23	Mark Rose	NF	no factor from 2^62 to 2^63
2015-09-29	ramgeis	NF	no factor from 2^65 to 2^66
2015-07-21	MadPoo	C-LL	EE4A1172BB5EAA40
2015-02-24	VictordeHollander	NF-PM1	B1=10000000, B2=200000000, E=12
2015-01-26	snme2pm1	NF	no factor from 2^64 to 2^65
2015-01-26	snme2pm1	NF	no factor from 2^63 to 2^64
2013-11-20	David Campeau	NF-PM1	B1=945000, B2=27405000, E=12
2011-01-28	James Heinrich	NF-PM1	B1=80000, B2=1340000, E=6
2010-04-04	GrunwalderGIMP	NF	no factor from 2^1 to 2^63

Username
Password