is 2 7887823 - 1
has 2374472 decimal digits
takes 1.805 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L2C276BB65B095B92double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual274485.034468.9189 %2800000203872305037.73198.1506 %522.766371.4522 %
Target2673.767165.6716 %5500060000000.12572.5611 %3.892866.5508 %
Difference+7+481.2674+3.2473 %+2745000+2032723050+37.6061+5.5896%+518.8735+4.9014 %

Known prime factors (1 factor, 81.0 bits, 0.00102649% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
788782323636997634540152491133372580.967149832201068280516
22 × 3 × 971 × 179351 × 71696983
2022-12-291793517169698351,8471.35232.4207

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2002-05-18Stephen Woodv4_computers4000040000--0.0130.673%
2011-04-22James HeinrichQ660015500033712506--0.1103.885%
2022-12-29yoyorocks1Manual testing2800000203872305022580.96745.5813.615%


Trial Factoring results:
575859606162636465666768697071727374
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-04-02ANONYMOUSv4_computers212630.124
2013-10-05NesowaManual testing2632640.249
2013-12-19David CampeauManual testing2642650.474
2015-06-09VictordeHollanderManual testing2652660.947
2016-08-31Gordon SpenceManual testing2662671.895
2018-08-05ramgeisManual testing2672683.790
2020-02-07TJAOIManual testing2682697.579
2021-08-21SRBaseManual testing26927015.16
2021-09-06SRBaseManual testing27027130.32
2021-09-30SRBaseManual testing27127260.63
2022-04-10TheJudgerManual testing272274363.8


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)
1999-08-31ANONYMOUSv4_computers2C276BB65B095B921.805
2002-06-09Stephen Woodv4_computers2C276BB65B095B921.805


PRP results:
dateuseridcompidcofactorsres64
2023-01-03Perigbrollach
2363699763454015249113337
2BDB984B7BF0DFBC


CERT results:
dateuseridcompid
2023-01-04Ben Deloi-018288def4b216d08


P-1 factor-bounds graph:
B1 = 2800000, B2 = 2038723050 (P-1 stage 2)
B1 = 2800000 (P-1 stage 1)
B1 = 155000, B2 = 3371250 (P-1 stage 2)
B1 = 155000 (P-1 stage 1)
B1 = 40000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
274
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
250
260
270
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290
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Last modified: 2024-03-13T02:15:48+00:00