is 2 8637061 - 1
has 2600015 decimal digits
takes 2.255 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L3941A0572E2FAE60double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual2686.901164.7059 %10000018250000.07342.8563 %6.974565.7140 %
Target2686.901164.7059 %5500060000000.14352.2943 %7.044565.5156 %
Difference---+45000-4175000-0.0700+0.5620%-0.0700+0.1984 %

Known prime factors (1 factor, 72.9 bits, 0.00084407% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
863706188306232118257721695592272.903511205328515439
33 × 37 × 511717045561
2019-08-0337511717045561110.7210,55619,715

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2002-11-24ANONYMOUSv4_computers40000420000--0.0231.612%
2012-02-13bcp19Turion_x210000018250006--0.0732.856%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-10-25ANONYMOUSv4_computers212620.036
1999-03-26ANONYMOUSv4_computers212630.114
1999-12-15ANONYMOUSv4_computers212640.227
2014-01-26lycornManual testing2642650.433
2015-05-25VictordeHollanderManual testing2652660.865
2016-02-04snme2pm1Manual testing2662671.730
2018-04-22monstManual testing2672683.461


ECM factoring results:
Total ECM effort:1.588 GHz-days
Estimated T-Level:0.769
DigitsB1CompleteFacMiss
20110000.15485.740%
25500000.01498.587%


ECM Summary

B1B2factorcurvesGHz-days
50000500000031.191
50000500000010.397


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2000-02-01ANONYMOUSv4_computers3941A0572E2FAE602.255
2002-12-09ANONYMOUSv4_computers3941A0572E2FAE602.255


PRP results:
dateuseridcompidcofactorsres64
2019-08-03ATHec2-PRPCF
8830623211825772169559
C2CB6713C9B6B610
2020-08-11kutensterra
8830623211825772169559
C2CB6713C9B6B610


CERT results:
No CERT results for M8637061


P-1 factor-bounds graph:
B1 = 100000, B2 = 1825000 (P-1 stage 2)
B1 = 100000 (P-1 stage 1)
B1 = 40000, B2 = 420000 (P-1 stage 2)
B1 = 40000 (P-1 stage 1)
100
101
102
103
104
105
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
TF factor-bounds graph:
268
267
266
265
264
263
262
this exponent TF target: 68
TF double-checked to: 67
ECM T-Level=0.77 ~= -14-bit
250
260
270
280
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Last modified: 2024-02-09T03:30:02+00:00