is 2 81331 - 1
has 24484 decimal digits
takes 0.000 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
-unknown- primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actualunknown1000000000205299781186502,434.858973.1044%2,434.858973.1044%73.1044%
PrimeNet2400.000057.5000%900130000.00006.6833%0.000060.3404%2.8404%
GPU722440.000061.3636%500100000.00002.3419%0.000062.2684%0.9048%
Difference-440.0000-61.3636%+999999500+20529978108650+2,434.8589+70.7625%+2,434.8589+10.8359%+72.1995%

Known prime factors (2 factors, 171.0 bits, 0.21026404% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
813311475786795279591547.068907272009
34 × 7 × 31 × 71 × 727
-817270.00032.527e-73.585e-7
813312042068813201971184099560779979815518338123.941125540618780168151387512804464461
3 × 118529 × 15509479 × 17445089 × 1304872237913
2022-01-231744508913048722379131.664e+12154.66288.80

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
8133130136581895757327609477848877565083069177774692614
97
52171.010
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-10-31T18:19:06kkmrkkblmbrbkManual testing100000000200000000012-
skipped known factor: 147578679527959
--0.443--40.394%
2022-01-23T18:51:44George WoltmanManual testing10000000002052997811865038123.9412,4350.0004,87064.654%


Trial Factoring results:
No TF results for M81331


ECM factoring results:
Total ECM effort:10.839 GHz-days
Estimated T-Level:30.997
DigitsB1CompleteFacMiss
201100094.9900.000%
255000015.4390.000%
302500001.93214.491%
3510000000.19981.923%
4030000000.01898.262%
45110000000.00199.867%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002810.440
250000250000005854.578
10000001000000001865.822


Lucas-Lehmer results:
No L-L results for M81331


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-21T20:31:35Oliver KrusePRP
147578679527959
60D3194D49141C__no
2017-09-21T21:30:06Oliver KruseManual testing
147578679527959
60D3194D49141C__no
2017-10-13T08:19:25kkmrkkblmbrbkManual testing
147578679527959
60D3194D49141C__no
2020-04-17T15:18:51Oliver KruseAddPrpType5
147578679527959
4433D507D613E7__no
2022-01-23T18:56:30mikrNitron
147578679527959
20420688132019711840995607799798155183
4433D507D613E740no


P-1 factor-bounds graph:
B1 = 1000000000, B2 = 20529978118650 (P-1 stage 2)
B1 = 1000000000 (P-1 stage 1)
B1 = 100000000, B2 = 2000000000 (P-1 stage 2)
B1 = 100000000 (P-1 stage 1)
100
101
102
103
104
105
106
107
108
109
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
1013
1014
TF factor-bounds graph:
240
250
260
270
280
290
2100
2110
2120
2130
Last modified: 2022-01-23T18:57:17+00:00