20 173 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
121039	6	16.9	old
525947712473	12	38.9	2008-08-26 19:58:58
3733330406447	13	41.8	2008-08-26 19:58:58
41363606209490205247055987452553	32	105.0	2017-10-10 15:26:00
242259284775981115080842803960207	33	107.6	2016-09-06 14:27:58
564294434675572061306080966980839	33	108.8	2017-10-10 09:21:55

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	640 / 640
35	1000000	1566 / 1566
40	3000000	4588 / 4588
45	11000000	1614 / 9201

Estimated T-Level: 40.9 ⓘ

TF below 2^131 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified (Factored)	2017-09-21	Oliver Kruse	FBD872B450B7F4B5	4	0	1	3
Verified (Factored)	2017-10-02	kkmrkkblmbrbk	FBD872B450B7F4B5	4	0	1	3
Verified (Factored)	2017-10-10	Oliver Kruse	CFF7105609C863CF	1	0	1	3
Verified	2017-10-10	alpertron	73AE80B78A44D539	6	0	1	3
Verified	2017-10-10	Chang Chia-Tche	73AE80B78A44D539	6	0	1	3
Verified	2017-10-11	George Woltman	73AE80B78A44D539	6	4399	1	3
Unverified	2020-04-17	Oliver Kruse	B9177145D29E26__	6	4461	5	3

P-1 factors

Date	Factor	B1	B2
2016-09-06	242259284775981115080842803960207	50000000	5000000000

History

Date	User	Type	Result
2023-08-11	nordi	NF-PM1	B1=12000000000, B2=3601049663361150
2023-04-20	nordi	NF-PM1	B1=12000000000
2020-04-17	Oliver Kruse	C-PRP	M20173/121039/525947712473/3733330406447/41363606209490205247055987452553/242259284775981115080842803960207/564294434675572061306080966980839 : B9177145D29E26__ PRP without proof (small exponent)
2017-10-11	George Woltman	C-PRP	M20173/121039/525947712473/3733330406447/242259284775981115080842803960207/564294434675572061306080966980839/41363606209490205247055987452553 : 73AE80B78A44D539 PRP without proof (small exponent)
2017-10-10	Chang Chia-Tche	C-PRP	M20173/known_factors : 73AE80B78A44D539 PRP without proof (not generated)
2017-10-10	alpertron	C-PRP	M20173/121039/525947712473/3733330406447/41363606209490205247055987452553/242259284775981115080842803960207/564294434675572061306080966980839 : 73AE80B78A44D539 PRP without proof (not generated)
2017-10-10	kkmrkkblmbrbk	F-ECM	Factor: 41363606209490205247055987452553 / (ECM curve 296, B1=1000000, B2=100000000)
2017-10-10	Oliver Kruse	C-PRP	M20173/known_factors : CFF7105609C863CF PRP without proof (not generated)
2017-10-10	kkmrkkblmbrbk	F-ECM	Factor: 564294434675572061306080966980839 / (ECM curve 99, B1=1000000, B2=100000000)
2017-10-02	kkmrkkblmbrbk	C-PRP	M20173/121039/525947712473/3733330406447/242259284775981115080842803960207 : FBD872B450B7F4B5 PRP without proof (not generated)
2017-09-21	Oliver Kruse	C-PRP	M20173/121039/525947712473/3733330406447/242259284775981115080842803960207 : FBD872B450B7F4B5 PRP without proof (not generated)
2016-11-12	kkmrkkblmbrbk	NF-PM1	B1=500000000, B2=10000000000, E=12
2016-09-06	kkmrkkblmbrbk	F-PM1	Factor: 242259284775981115080842803960207 / (P-1, B1=50000000, B2=5000000000, E=12)
2008-08-26	-Anonymous-	F	Factor: 3733330406447
2008-08-26	-Anonymous-	F	Factor: 525947712473