is 2 2054471 - 1
has 618458 decimal digits
takes 0.135 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LD7D3A888A3451B40double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26829.012369.1176%36000001800000001.25958.5629%30.271871.7621%2.6444%
PrimeNet2580.018763.7931%90001600000.00162.6667%0.020364.7586%0.9655%
GPU722620.299066.1290%90001200000.00141.3309%0.300566.5798%0.4508%
Difference+6+28.7132+2.9886%+3591000+179880000+1.2580+7.2320%+29.9713+5.1822%+5.1822%

Known prime factors (1 factor, 75.1 bits, 0.00365705% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2054471414256721792426658173112375.13310081834248145305
3 × 5 × 487 × 1380127891601
2020-06-2948713801278916014,679.97,168.713,389

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-02-24T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.222%
2006-01-15T00:00:00Jocelyn Larouchev4_computers40004000---0.000--0.047%
2009-05-24T19:26:00Rob_Deetwopc20000280000---0.003--0.893%
2010-12-26T02:29:00Jocelyn LaroucheManual testing3000030000---0.003--0.350%
2011-01-06T01:06:00Jocelyn LaroucheManual testing5000050000---0.005--0.508%
2011-01-21T07:54:00James Heinrichi7-9201350002902500---0.027--2.716%
2014-10-26T00:59:00Jocelyn LaroucheManual testing166241166241---0.016--1.058%
2016-05-15T21:00:26Jocelyn LaroucheManual testing27000048600006---0.050--3.413%
2016-09-22T12:02:51Jocelyn Larouchelow 4M27000058320006---0.055--3.550%
2016-11-06T00:28:17Jocelyn Larouchelow 4M324000324000---0.031--1.482%
2017-01-29T16:31:00mikrMSI250000012500000012---0.875--7.881%
2017-02-24T12:35:57mikrS052360000018000000012---1.259--8.563%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2016-02-23T16:29:04Mark RoseManual testing21260--0.075--
2009-01-02T10:16:00Sturle Sundegorky.ifi260261--0.075--
2012-03-11T11:47:00Sebastian HornbostelManual testing261262--0.150--
2013-09-01T20:20:00ramgeisManual testing262263--0.478--
2015-04-21T09:19:00VictordeHollanderManual testing263264--0.956--
2015-04-21T09:19:00VictordeHollanderManual testing264265--1.819--
2015-11-03T10:10:00ramgeisManual testing265266--3.637--
2016-08-18T20:55:11Gordon SpenceManual testing266267--7.275--
2019-03-24T00:15:07chuenkitManual testing267268--14.55--


ECM factoring results:

Old Calculation Method

Total ECM effort:8.911 GHz-days
Estimated T-Level:21.875
DigitsB1CurvesCompleteFacMiss
2011000105 / 1001.05034.809%
2550000105 / 2800.37568.683%

New Calculation Method

Total ECM effort:8.911 GHz-days
Estimated T-Level:21.875
DigitsB1CompleteFacMiss
20110003.3873.381%
25500000.30673.630%
302500000.01998.133%


ECM Summary

B1B2factorcurvesGHz-days
5000050000001028.656
50000500000030.255


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2015-11-13T21:36:48MadPooManual testingD7D3A888A3451B400.135


PRP results:
dateuseridcompidcofactorsres64PRP
2020-06-30T10:36:40Christoph ZengerManual testing
41425672179242665817311
9E94347F87178BCDno
2020-06-30T19:30:56Yuji Hasegawavj22m
41425672179242665817311
9E94347F87178BCDno


P-1 factor-bounds graph:
B1 = 3600000, B2 = 180000000 (P-1 stage 2)
B1 = 2500000, B2 = 125000000 (P-1 stage 2)
B1 = 3600000 (P-1 stage 1)
B1 = 2500000 (P-1 stage 1)
B1 = 270000, B2 = 5832000 (P-1 stage 2)
B1 = 270000, B2 = 4860000 (P-1 stage 2)
B1 = 324000 (P-1 stage 1)
B1 = 135000, B2 = 2902500 (P-1 stage 2)
B1 = 270000 (P-1 stage 1)
B1 = 166241 (P-1 stage 1)
B1 = 135000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 20000, B2 = 280000 (P-1 stage 2)
B1 = 30000 (P-1 stage 1)
B1 = 20000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 4000 (P-1 stage 1)
B1 = 2048 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2020-06-30T19:30:56+00:00