is 2 8712373 - 1
has 2622686 decimal digits
takes 2.275 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L659C87A70BCD36C7double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual2673.410564.1791 %16000033200000.12583.9436 %3.536365.5917 %
Target2686.841464.7059 %5500060000000.14352.2975 %6.984965.5168 %
Difference-1-3.4309-0.5268 %+105000-2680000-0.0177+1.6461%-3.4486+0.0750 %

Known prime factors (1 factor, 71.7 bits, 0.00082281% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
871237338001738026269191114172271.687218090628272396
22 × 11 × 4956605188009
2013-12-0111495660518800954.873102,244190,963

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2002-12-02ANONYMOUSv4_computers4500072000012--0.0311.928%
2002-12-09ANONYMOUSv4_computers4500072000012--0.0311.928%
2012-05-25James Heinrichi7-92016000033200006--0.1263.539%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-10-25Sturle Sundev4_computers212620.035
1999-03-26ANONYMOUSv4_computers212630.113
1999-10-29ANONYMOUSv4_computers212640.225


ECM factoring results:
Total ECM effort:1.191 GHz-days
DigitsB1CompleteFacMiss


ECM Summary

B1B2factorcurvesGHz-days
11.191


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-12-01ANONYMOUSv4_computers659C87A70BCD36C72.275
2002-12-09ANONYMOUSv4_computers659C87A70BCD36C72.275


PRP results:
dateuseridcompidcofactorsres64
2019-01-02GunnarLuSierpinski
3800173802626919111417
8B6D45A95A16187C
2020-08-25marssystemssystem03
3800173802626919111417
8B6D45A95A16187C


CERT results:
No CERT results for M8712373


P-1 factor-bounds graph:
B1 = 160000, B2 = 3320000 (P-1 stage 2)
B1 = 160000 (P-1 stage 1)
B1 = 45000, B2 = 720000 (P-1 stage 2)
B1 = 45000 (P-1 stage 1)
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TF factor-bounds graph:
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this exponent TF target: 68
TF double-checked to: 67
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Last modified: 2024-02-29T14:28:04+00:00