is 2 2618813 - 1
has 788342 decimal digits
takes 0.202 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L912BC4451C425847double-checked
PRP3EB15D5DB566D280verified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26822.760367.6471%2618813261881300.43716.2127%23.197469.6570%2.0100%
PrimeNet2590.029362.7119%110002000000.00242.6985%0.031763.7181%1.0062%
GPU722630.609465.0794%120002000000.00251.5325%0.611965.6145%0.5352%
Difference+5+22.1508+2.5677%+2606813+25988130+0.4346+4.6802%+22.5854+4.0425%+4.0425%

Known prime factors (1 factor, 80.0 bits, 0.00305639% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
261881312439304485830928424531032580.041237498906677012227
13 × 18269146667462479
2020-08-10131826914666746247998,502111,471,990208,198,634

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-31T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.238%
2003-11-08T00:00:00Team Prime Ribv4_computers15000217500---0.003--0.782%
2010-11-17T22:12:00Jocelyn LaroucheManual testing2000020000---0.002--0.266%
2010-12-12T12:03:00markrtiny1000002125000---0.024--2.474%
2014-10-13T22:29:00Jocelyn LaroucheManual testing124509124509---0.014--0.942%
2016-05-24T01:15:57Jocelyn LaroucheManual testing20000036000006---0.043--3.156%
2017-07-20T22:03:19Jocelyn Larouchelow 4M40000040000006---0.067--3.546%
2019-10-14T15:57:33masserManual testing26188132618813012---0.437--6.213%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-26T00:00:00ANONYMOUSv4_computers21259--0.029--
2016-02-23T16:29:17Mark RoseManual testing259260--0.029--
2009-01-30T22:39:00Sturle Sundegiovanni.ifi260261--0.059--
2012-06-18T11:53:00markroldgamer261262--0.117--
2013-01-23T08:30:00dbaughManual testing262263--0.375--
2015-02-18T11:41:00VictordeHollanderManual testing263264--0.750--
2015-02-18T11:41:00VictordeHollanderManual testing264265--1.427--
2016-01-17T23:07:15ramgeisManual testing265266--2.853--
2016-03-16T15:50:16YxinityManual testing266267--5.707--
2019-04-15T13:43:00TJAOIManual testing267268--11.41--


ECM factoring results:

Old Calculation Method

Total ECM effort:5.154 GHz-days
Estimated T-Level:2.500
DigitsB1CurvesCompleteFacMiss
201100050 / 1000.50060.501%
255000050 / 2800.17983.620%

New Calculation Method

Total ECM effort:5.154 GHz-days
Estimated T-Level:2.500
DigitsB1CompleteFacMiss
20110001.61319.931%
25500000.14686.435%
302500000.00999.106%


ECM Summary

B1B2factorcurvesGHz-days
500005000000484.948
50000500000020.206


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-04-23T00:00:00ANONYMOUSv4_computers912BC4451C4258470.202
2000-03-15T00:00:00ANONYMOUSv4_computers912BC4451C4258470.202


PRP results:
dateuseridcompidcofactorsres64PRP
2020-08-10T15:54:38CrypticCluecruncher
1243930448583092842453103
3EB15D5DB566D280no


P-1 factor-bounds graph:
B1 = 2618813, B2 = 26188130 (P-1 stage 2)
B1 = 2618813 (P-1 stage 1)
B1 = 400000, B2 = 4000000 (P-1 stage 2)
B1 = 400000 (P-1 stage 1)
B1 = 200000, B2 = 3600000 (P-1 stage 2)
B1 = 100000, B2 = 2125000 (P-1 stage 2)
B1 = 200000 (P-1 stage 1)
B1 = 124509 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 15000, B2 = 217500 (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: 2020-08-10T15:54:38+00:00