Marin Mersenne 2^P-1
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Finding World Record Primes Since 1996

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Exponent Range:










MnStatusDetails
1861Composite, with 4 known prime factors. Cofactor is composite.
Factored
FactorDigitsBitsDate
1023551720.0old
2735671721.4old
333842300941257284791947372684.8old
5725904826074495849672174509373098.9old
ECM
DigitsB1Curves
2550000280 / 280
30250000640 / 640
3510000001566 / 1566
4030000004588 / 4588
45110000009201 / 9201
504400000016550 / 16550
5511000000040830 / 40830
60260000000105362 / 105362
6580000000066866 / 194238
Estimated T-Level: 61.7
TF below 2^200 is very unlikely to find new factors due to ECM effort.
PRP Cofactor
StatusDateUserResidueNumber of
known factors
ShiftTypeBase
Verified2017-09-21Oliver KruseD614AD651F8B140D4013
Verified2017-10-02kkmrkkblmbrbkD614AD651F8B140D4013
Verified2017-12-07ATHD614AD651F8B140D450413
Verified2020-04-17Oliver Kruse1558D7A7DDFC480B453553
Verified2020-08-12_p95holder_1558D7A7DDFC480B423253
History
DateUserTypeResult
2022-11-03mikrNF-PM1
B1=400000000000, B2=2575888041040674360
2021-07-25ViliamFNF-PP1
Start=2/7, B1=1000000000, B2=221000000000
2020-08-12_p95holder_C-PRP
M1861/1023551/2735671/33384230094125728479194737/572590482607449584967217450937 : 1558D7A7DDFC480B
PRP: Verified
PRP without proof (small exponent)
2020-04-17Oliver KruseC-PRP
M1861/1023551/2735671/33384230094125728479194737/572590482607449584967217450937 : 1558D7A7DDFC480B
PRP: Verified
PRP without proof (small exponent)
2017-12-07ATHC-PRP
M1861/1023551/2735671/33384230094125728479194737/572590482607449584967217450937 : D614AD651F8B140D
PRP: Verified
PRP without proof (small exponent)
2017-10-02kkmrkkblmbrbkC-PRP
M1861/1023551/2735671/33384230094125728479194737/572590482607449584967217450937 : D614AD651F8B140D
PRP: Verified
PRP without proof (not generated)
2017-09-21Oliver KruseC-PRP
M1861/known_factors : D614AD651F8B140D
PRP without proof (not generated)
2016-09-07kkmrkkblmbrbkNF-PM1
B1=1000000000, B2=100000000000, E=12