is 2 2554583 - 1
has 769007 decimal digits
takes 0.177 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L84027A32D3892304double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26823.332567.6471%32000001120000000.91808.0743%24.250570.2593%2.6123%
PrimeNet2590.030162.7119%110002000000.00212.6861%0.032263.7135%1.0016%
GPU722630.624865.0794%120001800000.00211.4785%0.626965.5957%0.5163%
Difference+5+22.7078+2.5677%+3188000+111820000+0.9159+6.5957%+23.6236+4.6636%+4.6636%

Known prime factors (1 factor, 71.8 bits, 0.00280948% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
255458340276179778302096839532271.770788312217264072
23 × 3 × 67 × 1429 × 343067821
2020-07-231429343067821216.811.88003.5110

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-23T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.236%
2003-11-08T00:00:00Team Prime Ribv4_computers15000198750---0.003--0.756%
2010-12-19T21:44:00Jocelyn LaroucheManual testing2000020000---0.002--0.265%
2011-01-03T14:35:00Jocelyn LaroucheManual testing3000030000---0.003--0.367%
2011-01-09T14:30:00Jocelyn LaroucheManual testing5000050000---0.005--0.531%
2011-04-09T23:50:00James HeinrichWHS1750004068750---0.039--3.163%
2016-03-31T11:13:19mikrMSI320000011200000012---0.918--8.074%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:16Mark RoseManual testing259260--0.030--
2009-01-30T19:19:00Sturle Sundegorky.ifi260261--0.060--
2012-06-16T18:43:00Sebastian HornbostelManual testing261262--0.120--
2013-01-23T08:30:00dbaughManual testing262263--0.384--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.769--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.463--
2015-11-04T20:25:08omylistManual testing265266--2.925--
2017-08-10T07:53:54Gordon SpenceManual testing266267--5.850--
2019-06-03T11:26:13TJAOIManual testing267268--11.70--


ECM factoring results:

Old Calculation Method

Total ECM effort:4.519 GHz-days
Estimated T-Level:2.450
DigitsB1CurvesCompleteFacMiss
201100049 / 1000.49061.112%
255000049 / 2800.17583.919%

New Calculation Method

Total ECM effort:4.519 GHz-days
Estimated T-Level:2.450
DigitsB1CompleteFacMiss
20110001.58120.584%
25500000.14386.688%
302500000.00999.124%


ECM Summary

B1B2factorcurvesGHz-days
500005000000484.427
50000500000010.092


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-04-13T00:00:00ANONYMOUSv4_computers84027A32D38923040.177
2018-06-12T13:38:25kkmrkkblmbrbkold84027A32D38923040.177


PRP results:
dateuseridcompidcofactorsres64PRP
2020-07-23T14:37:37CrypticCluecruncher
4027617977830209683953
FE3009157F041C3Ano
2020-07-24T11:51:37marssystemssystem03
4027617977830209683953
FE3009157F041C3Ano


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 175000, B2 = 4068750 (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)
102
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105
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102
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105
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109
TF factor-bounds graph:
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266
265
264
263
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261
260
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260
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2100
Last modified: 2020-07-24T11:51:37+00:00