is 2 7865623 - 1
has 2367789 decimal digits
takes 1.800 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LDB214DE88C5895ABdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual2687.577966.1765 %10000019000000.06572.8436 %7.643667.1383 %
Target2673.777765.6716 %5500060000000.12572.5599 %3.903466.5504 %
Difference+1+3.8002+0.5048 %+45000-4100000-0.0600+0.2837%+3.7402+0.5878 %

Known prime factors (1 factor, 69.1 bits, 0.00087816% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
78656236208224115411468545192169.07339464287287933
3 × 691 × 1399 × 13607779
2018-09-0313991360777915.1780.24640.4594

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2002-05-25ANONYMOUSv4_computers35000192500--0.0141.379%
2012-09-10NesowaWork10000019000006--0.0663.192%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-06-06ANONYMOUSv4_computers212630.125
2013-10-05NesowaManual testing2632640.250
2013-12-16David CampeauManual testing2642650.475
2015-06-09VictordeHollanderManual testing2652660.950
2016-08-29Gordon SpenceManual testing2662671.900
2018-08-05ramgeisManual testing2672683.800


ECM factoring results:
Total ECM effort:2.088 GHz-days
Estimated T-Level:1.154
DigitsB1CompleteFacMiss
20110000.23179.392%
25500000.02197.887%
302500000.00199.865%


ECM Summary

B1B2factorcurvesGHz-days
50000500000031.044
50000500000031.044


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-08-07ANONYMOUSv4_computersDB214DE88C5895AB1.800
2002-06-29ANONYMOUSv4_computersDB214DE88C5895AB1.800


PRP results:
dateuseridcompidcofactorsres64
2018-09-05Chang Chia-Tchehomura
620822411541146854519
20B47359860DA18F
2019-10-28ATHec2-PRPCFDC
620822411541146854519
20B47359860DA18F


CERT results:
No CERT results for M7865623


P-1 factor-bounds graph:
B1 = 100000, B2 = 1900000 (P-1 stage 2)
B1 = 100000 (P-1 stage 1)
B1 = 35000, B2 = 192500 (P-1 stage 2)
B1 = 35000 (P-1 stage 1)
102
103
104
105
102
103
104
105
106
107
108
TF factor-bounds graph:
268
267
266
265
264
263
this exponent TF target: 67
TF double-checked to: 67
ECM T-Level=1.15 ~= -13-bit
250
260
270
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Last modified: 2024-02-09T03:30:02+00:00