is 2 2165857 - 1
has 651988 decimal digits
takes 0.142 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LDE073092C4A4C5B1double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26955.122268.1159 %5000000989699403051.858213.0642 %106.980472.2813 %
Target2620.283764.5161 %100008000000.00511.5201 %0.288765.0555 %
Difference+7+54.8385+3.5998 %+4990000+9896194030+51.8531+11.5441%+106.6917+7.2258 %

Known prime factors:
No known factors for M2165857

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-03-07ANONYMOUSv4_computers204820480012--0.0010.776%
2010-11-03JossManual testing2000020000--0.0020.712%
2010-12-30JossManual testing3000030000--0.0030.935%
2011-01-15JossManual testing5000050000--0.0051.272%
2011-01-21markrtiny12000023700006--0.0235.006%
2014-10-05JossManual testing149635149635--0.0142.219%
2016-03-04JossManual testing22445140401186--0.0416.011%
2017-09-05JossManual testing44890244890206--0.0646.540%
2018-01-06mikrMSI250000012500000012--0.87512.593%
2022-12-26Architects Cubedgpu7250000009896994030--54.7120.232%


Trial Factoring results:
57585960616263646566676869
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-01-29ANONYMOUSv4_computers212580.018
2016-02-23Mark RoseManual testing2582600.053
2009-01-04Sturle Sundemorovan.ifi2602610.071
2009-01-07Sturle Sundehomilius.ifi2612620.142
2013-09-08ramgeisManual testing2622630.453
2015-03-25VictordeHollanderManual testing2632652.632
2015-12-30ramgeisManual testing2652663.450
2016-11-10Gordon SpenceManual testing2662676.900
2019-05-06TJAOIManual testing26726813.80
2021-07-15TJAOIManual testing26826927.60


ECM factoring results:
Total ECM effort:17.554 GHz-days
Estimated T-Level:23.676
DigitsB1CompleteFacMiss
20110007.9460.035%
25500000.73547.945%
302500000.04695.468%
3510000000.00299.783%


ECM Summary

B1B2factorcurvesGHz-days
50000500000019916.87
50000675000070.684


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-29ANONYMOUSv4_computersDE073092C4A4C5B10.142
2018-04-11kkmrkkblmbrbkoldDE073092C4A4C5B10.142


PRP results:
No PRP results for M2165857


CERT results:
No CERT results for M2165857


P-1 factor-bounds graph:
B1 = 5000000, B2 = 9896994030 (P-1 stage 2)
B1 = 2500000, B2 = 125000000 (P-1 stage 2)
B1 = 5000000 (P-1 stage 1)
B1 = 2500000 (P-1 stage 1)
B1 = 448902, B2 = 4489020 (P-1 stage 2)
B1 = 448902 (P-1 stage 1)
B1 = 224451, B2 = 4040118 (P-1 stage 2)
B1 = 120000, B2 = 2370000 (P-1 stage 2)
B1 = 224451 (P-1 stage 1)
B1 = 149635 (P-1 stage 1)
B1 = 120000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 20000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
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1010
TF factor-bounds graph:
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258
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=23.68 ~= 62-bit
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Last modified: 2024-03-13T02:15:48+00:00