is 2 7878869 - 1
has 2371776 decimal digits
takes 1.803 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LA4F3022ADBCEDBE5double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272121.379668.0556 %2500000040052471550731.860715.0923 %853.240372.8767 %
Target2673.771365.6716 %5500060000000.12572.5606 %3.897166.5507 %
Difference+5+117.6082+2.3839 %+24945000+40046471550+731.7350+12.5317%+849.3432+6.3261 %

Known prime factors (1 factor, 93.7 bits, 0.00118956% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
7878869163539390902365932511044469212993.7241037835448859258432340
22 × 3 × 5 × 29 × 3343 × 321571 × 554837747
2022-03-21321571554837747502,584,07210.13118.733

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2009-08-10Carsten Kossendeymother450006975006--0.0302.141%
2012-10-08NesowaWork10000019000006--0.0663.193%
2021-10-14Architects Cubeda3_cont41100023398000--0.5526.368%
2022-03-21Oliver Kruse11700K250000004005247155022993.724884.019.974%


Trial Factoring results:
57585960616263646566676869707172
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-07-26delongv4_computers212630.125
2013-10-05NesowaManual testing2632640.249
2013-12-19David CampeauManual testing2642650.474
2015-06-09VictordeHollanderManual testing2652660.948
2016-08-31Gordon SpenceManual testing2662671.897
2018-08-05ramgeisManual testing2672683.794
2020-02-14TJAOIManual testing2682697.588
2021-08-20SRBaseManual testing26927015.18
2021-08-28SRBaseManual testing27027130.35
2021-10-15SRBaseManual testing27127260.70


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
50000500000062.088


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-11-17Nick Craig-Woodv4_computersA4F3022ADBCEDBE51.803


PRP results:
dateuseridcompidcofactorsres64
2022-03-22Oliver KruseServer-Phi
16353939090236593251104446921
D383F28B1CEECA2E


CERT results:
dateuseridcompid
2022-03-22Steve Jacobsoni5s2800


P-1 factor-bounds graph:
B1 = 25000000, B2 = 40052471550 (P-1 stage 2)
B1 = 25000000 (P-1 stage 1)
B1 = 411000, B2 = 23398000 (P-1 stage 2)
B1 = 411000 (P-1 stage 1)
B1 = 100000, B2 = 1900000 (P-1 stage 2)
B1 = 100000 (P-1 stage 1)
B1 = 45000, B2 = 697500 (P-1 stage 2)
B1 = 45000 (P-1 stage 1)
103
104
105
106
107
108
103
104
105
106
107
108
109
1010
1011
TF factor-bounds graph:
272
271
270
269
268
267
266
265
264
263
this exponent TF target: 67
TF double-checked to: 67
ECM T-Level=1.15 ~= -13-bit
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Last modified: 2024-03-13T02:15:48+00:00