is 2 2562803 - 1
has 771481 decimal digits
takes 0.178 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LA662CC5E3EA21281double-checked
PRPB48379635716E2C7verified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26946.584568.1159%32000001120000000.91807.4472%47.502570.4904%2.3745%
PrimeNet2590.030062.7119%110002000000.00212.6877%0.032163.7141%1.0022%
GPU722630.622865.0794%120001800000.00211.4795%0.624965.5960%0.5166%
Difference+6+45.9617+3.0366%+3188000+111820000+0.9159+5.9677%+46.8776+4.8944%+4.8944%

Known prime factors (1 factor, 79.6 bits, 0.00310457% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
25628038935516096352369976980632479.564174330920019064477
174330920019064477
2021-08-27117433092001906447789,725955,251,1191.784e+9

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-23T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.191%
2003-11-08T00:00:00Team Prime Ribv4_computers15000198750---0.003--0.645%
2010-12-21T01:09:00Jocelyn LaroucheManual testing2000020000---0.002--0.222%
2011-01-03T14:36:00Jocelyn LaroucheManual testing3000030000---0.003--0.311%
2011-01-10T23:57:00Jocelyn LaroucheManual testing5000050000---0.005--0.455%
2011-04-13T15:57:00James HeinrichWHS1750004112500---0.039--2.838%
2016-05-07T16:27:56mikrMSI320000011200000012---0.918--7.447%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-07-30T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:16Mark RoseManual testing259260--0.030--
2009-01-31T14:10:00Sturle Sundegowin.ifi260261--0.060--
2012-06-17T10:42:00Sebastian HornbostelManual testing261262--0.120--
2013-01-23T08:30:00dbaughManual testing262263--0.383--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.766--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.458--
2015-11-08T21:03:00ramgeisManual testing265266--2.916--
2017-08-13T10:39:19Gordon SpenceManual testing266267--5.832--
2019-06-17T12:14:54TJAOIManual testing267268--11.66--
2021-07-12T19:27:20TJAOIManual testing268269--23.33--


ECM factoring results:

Old Calculation Method

Total ECM effort:12.192 GHz-days
Estimated T-Level:22.339
DigitsB1CurvesCompleteFacMiss
2011000131 / 1001.31026.805%
2550000131 / 2800.46862.582%

New Calculation Method

Total ECM effort:12.192 GHz-days
Estimated T-Level:22.339
DigitsB1CompleteFacMiss
20110004.2491.428%
25500000.38468.128%
302500000.02497.664%
3510000000.00199.892%


ECM Summary

B1B2factorcurvesGHz-days
50000500000011310.43
50000500000040.369
50000515000070.654
50000675000070.742


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-06-15T00:00:00ANONYMOUSv4_computersA662CC5E3EA212810.178
2018-06-14T16:15:12kkmrkkblmbrbkoldA662CC5E3EA212810.178


PRP results:
dateuseridcompidcofactorsres64PRP
2021-08-28T19:57:58SRJ2877LTOS
893551609635236997698063
B48379635716E2C7no


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 175000, B2 = 4112500 (P-1 stage 2)
B1 = 175000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 198750 (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)
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TF factor-bounds graph:
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Last modified: 2021-08-28T19:57:58+00:00