is 2 2879687 - 1
has 866873 decimal digits
takes 0.222 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L7DB6591D222F24BCdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26710.318567.1642 %2400002798523001.73307.5177 %12.051469.6327 %
Target2630.554265.0794 %1600014000000.01021.8707 %0.564565.7326 %
Difference+4+9.7642+2.0848 %+224000+278452300+1.7227+5.6470%+11.4870+3.9000 %

Known prime factors (1 factor, 84.9 bits, 0.00294654% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2879687348893065566629274181173612684.8516057829645489757640
23 × 3 × 5 × 17 × 389 × 1187 × 3911 × 1644367
2011-02-25391116443671,395,8570.01040.0187

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-11-28ANONYMOUSv4_computers2048204800--0.0010.687%
2009-07-03Carsten Kossendeymother15000161250--0.0031.564%
2010-12-24JossManual testing2000020000--0.0020.642%
2011-01-27JossManual testing5000050000--0.0061.160%
2011-02-25Carsten Kossendeymother2684.8510.0510.000%
2023-04-16Kevin_9611Factor_2240000279852300
skipped known factor: 34889306556662927418117361
--2.02110.745%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2009-02-12Sturle Sundegideon.ifi2602610.053


ECM factoring results:
Total ECM effort:0.243 GHz-days
Estimated T-Level:0.577
DigitsB1CompleteFacMiss
20110000.11589.102%
25500000.01198.938%


ECM Summary

B1B2factorcurvesGHz-days
50000500000030.243


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-05-09ANONYMOUSv4_computers7DB6591D222F24BC0.222


PRP results:
dateuseridcompidcofactorsres64
2017-10-23Oliver KruseGTX-0
34889306556662927418117361
6408465207736781
2017-12-07ATHec2-1xh
34889306556662927418117361
6408465207736781


CERT results:
No CERT results for M2879687


P-1 factor-bounds graph:
B1 = 240000, B2 = 279852300 (P-1 stage 2)
B1 = 240000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 15000, B2 = 161250 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
103
104
105
106
102
103
104
105
106
107
108
109
TF factor-bounds graph:
261
this exponent TF target: 63
TF double-checked to: 67
ECM T-Level=0.58 ~= -15-bit
250
260
270
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290
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Last modified: 2024-03-13T02:15:48+00:00