is 2 641 - 1
has 193 decimal digits
takes 0.000 GHz-days to do one PRP test
Has been fully factored.
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 PRP tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP1A91EA6C4870D524PRP-tested
Cofactor is a certified prime

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26746,355.565685.0746%----46,355.565685.0746%
Target2440.003777.2727%500800000.00000.5220%0.003777.3914%
Difference+23+46,355.5619+7.8019%-500-800000.0000-0.5220%+46,355.5619+7.6833%

Known prime factors (6 factors, 641.0 bits, 100.00000000% known):
Remaining cofactor is a certified-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
64135897515.13228
22 × 7
-476.851e-126.138e-111.200e-10
64149999515.61039
3 × 13
-3136.867e-125.226e-119.001e-11
64111738350971030.129915628
22 × 7 × 53 × 617
-536172.651e-71.234e-91.590e-9
64124012588919495266859261514412890.9561873056857994950613046920
23 × 32 × 5 × 5202935716652640591797
-952029357166526405917975.487e+114.179e+97.805e+9
64174527630073444060622638692431221317567790318279733
4854064486587296999
69228.78958133876812358861640123785047754537884391823931149
3645916136183539

109 × 617 × 4357 × 24185176129 × 2217111847817 × 36999274377418301479471549107607363
-2217111847817369992743774183014794715491076073632.371e+142.972e+225.550e+22
641
hide decimal representation
2420161564200739329410254310444778820196576654139080232429544162649795567983079
79260.385

26 Composite Factors:
P-1 results:
No P-1 results for M641


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-06-20ANONYMOUSv4_computers??60.8701941.232.80346e-8177.4
1999-04-13Johnson Lauv4_computers??60.8701941.232.80346e-8177.4
2001-03-11ANONYMOUSv4_computers??60.8701941.232.80346e-8177.4
2001-11-10ANONYMOUSv4_computers??60.8701941.232.80346e-8177.4


ECM factoring results:
No ECM results for M641


Lucas-Lehmer results:
No L-L results for M641


PRP results:
dateuseridcompidcofactorsres64PRP
2018-01-24Luke_Richardswork-laptop1A91EA6C4870D524no


P-1 factor-bounds graph:
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
1013
100
101
102
103
104
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109
1010
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1016
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1020
1021
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1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
TF factor-bounds graph:
2
this exponent TF target: 44
TF double-checked to: 67.9
250
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2100
2110
2120
2130
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2200
Last modified: 2023-07-11T14:45:05+00:00