is 2 6918187 - 1
has 2082582 decimal digits
takes 1.509 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L19ED872F115739D3double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual272138.234768.0556%40000004143239108.33317.9711%146.567870.6019%2.5463%
PrimeNet2630.230763.4921%280007000000.02043.1599%0.251164.6457%1.1536%
GPU722674.295065.6716%450009000000.02902.2362%4.324066.4393%0.7676%
Difference+5+133.9397+2.3839%+3955000+413423910+8.3042+5.7349%+142.2438+4.1626%+1.7787%

Known prime factors:
No known factors for M6918187

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-10-20T00:00:00ANONYMOUSv4_computers35000341250---0.016--0.798%
2011-11-21T05:56:00James Heinrichi7-9201300002665000---0.085--1.986%
2020-01-11T02:20:21takahashivaio6000001200000012---0.386--3.581%
2021-11-24T18:20:29Seth_TrManual testing400000011000000012---3.091--6.530%
2021-12-02T06:48:51Seth_TrManual testing4000000414323910---8.333--7.971%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-07-21T00:00:00ANONYMOUSv4_computers21262--0.089--
2000-02-01T00:00:00ANONYMOUSv4_computers21263--0.231--
2014-02-09T10:09:00NesowaManual testing263264--0.284--
2014-02-17T19:28:00lycornManual testing264265--0.540--
2015-06-26T13:39:00VictordeHollanderManual testing265266--1.080--
2016-04-02T19:16:00Gordon SpenceManual testing266267--2.160--
2018-02-27T00:21:35-Anonymous-Manual testing267268--4.321--
2020-05-15T09:09:06TJAOIManual testing268269--8.641--
2021-07-18T04:15:08takahashiManual testing269270--17.28--
2021-08-12T16:26:58SRBaseManual testing270271--34.57--
2021-10-24T07:46:45SRBaseManual testing271272--69.13--


ECM factoring results:
Total ECM effort:1.989 GHz-days
Estimated T-Level:1.154
DigitsB1CompleteFacMiss
20110000.23179.392%
25500000.02197.887%
302500000.00199.865%


ECM Summary

B1B2factorcurvesGHz-days
50000500000061.989


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-15T00:00:00ANONYMOUSv4_computersD29B94DE19B2AE__1.509
2000-11-15T00:00:00ANONYMOUSv4_computers19ED872F115739D31.509
2002-03-31T00:00:00mhoneyv4_computers19ED872F115739D31.509


PRP results:
No PRP results for M6918187


P-1 factor-bounds graph:
B1 = 4000000, B2 = 414323910 (P-1 stage 2)
B1 = 4000000, B2 = 110000000 (P-1 stage 2)
B1 = 4000000 (P-1 stage 1)
B1 = 600000, B2 = 12000000 (P-1 stage 2)
B1 = 600000 (P-1 stage 1)
B1 = 130000, B2 = 2665000 (P-1 stage 2)
B1 = 130000 (P-1 stage 1)
B1 = 35000, B2 = 341250 (P-1 stage 2)
B1 = 35000 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2021-12-02T06:48:51+00:00