Marin Mersenne 2^P-1
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MnStatusDetails
21851Composite, with 1 known prime factor. Cofactor is composite.
Factored
FactorDigitsBitsDate
9254877247443382172896047582569981287338126.12009-08-24 15:56:31
ECM
DigitsB1Curves
2550000280 / 280
30250000640 / 640
3510000001566 / 1566
4030000004588 / 4588
45110000009201 / 9201
50440000002333 / 16550
Estimated T-Level: 45.7
TF below 2^147 is very unlikely to find new factors due to ECM effort.
LL
StatusDateUserResidueShift
Verified (Factored)Unknown5BFC0
Verified (Factored)George WoltmanAFF9F85412C6DBFC0
Verified (Factored)Brian J. BeesleyAFF9F85412C6DBFC0
PRP Cofactor
StatusDateUserResidueNumber of
known factors
ShiftTypeBase
Verified2017-09-21Oliver Kruse8445D0D70368BFBB1013
Verified2017-10-12kkmrkkblmbrbk8445D0D70368BFBB12099513
Verified2020-04-17Oliver Kruse81923ACAD13CCF2611267253
Verified2024-07-01kkmrkkblmbrbk81923ACAD13CCF261215353
History
DateUserTypeResult
2024-07-01kkmrkkblmbrbkC-PRP
M21851/92548772474433821728960475825699812873 : 81923ACAD13CCF26
PRP: Verified
PRP without proof (small exponent)
2023-09-29nordiNF-PM1
B1=12000000000, B2=3602870096075250
2023-04-14nordiNF-PM1
B1=12000000000
2022-05-06LordJuliusNF
no factor from 2^57 to 2^58
2021-06-28ATHNF-PP1
Start=2/7, B1=100000000, B2=10000000000
2020-04-17Oliver KruseC-PRP
M21851/92548772474433821728960475825699812873 : 81923ACAD13CCF26
PRP: Verified
PRP without proof (small exponent)
2017-10-12kkmrkkblmbrbkC-PRP
M21851/92548772474433821728960475825699812873 : 8445D0D70368BFBB
PRP: Verified
PRP without proof (not generated)
2017-09-21Oliver KruseC-PRP
M21851/92548772474433821728960475825699812873 : 8445D0D70368BFBB
PRP: Verified
PRP without proof (not generated)
2017-09-21Oliver KruseC-PRP
M21851/92548772474433821728960475825699812873 : 8445D0D70368BFBB
PRP without proof (not generated)
2016-11-18kkmrkkblmbrbkNF-PM1
B1=500000000, B2=10000000000, E=12
2009-08-24-Anonymous-F-ECM
Factor: 92548772474433821728960475825699812873
2009-02-11Sturle SundeNF
no factor from 2^59 to 2^60
2009-01-18Sturle SundeNF
no factor from 2^58 to 2^59