is 2 6908281 - 1
has 2079600 decimal digits
takes 1.506 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LC93FEDC52AECBACFdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual272138.432968.0556%40000004568186709.06528.0768%147.498170.6357%2.5801%
PrimeNet2630.231063.4921%280007000000.02043.1592%0.251564.6454%1.1533%
GPU722674.301265.6716%450009000000.02902.2357%4.330266.4391%0.7675%
Difference+5+134.1317+2.3839%+3955000+455918670+9.0362+5.8412%+143.1679+4.1965%+1.8126%

Known prime factors:
No known factors for M6908281

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-08-24T00:00:00Sturle Sundev4_computers35000437500---0.018--0.863%
2012-08-11T10:36:00NesowaEPC850001487500---0.051--1.559%
2018-03-15T17:42:03Squeeky_Squirreli5-5250U_16004050001225125012---0.332--3.404%
2021-11-18T05:18:55Seth_TrManual testing30000007500000012---2.189--5.980%
2021-11-30T02:54:15Seth_TrManual testing4000000456818670---9.065--8.077%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-06-29T00:00:00ANONYMOUSv4_computers21261--0.044--
1998-07-11T00:00:00ANONYMOUSv4_computers21262--0.089--
2005-07-01T00:00:00ANONYMOUSv4_computers21263--0.231--
2014-02-09T10:09:00NesowaManual testing263264--0.284--
2014-02-18T07:34:00lycornManual testing264265--0.541--
2015-06-21T19:55:00VictordeHollanderManual testing265266--1.082--
2016-04-01T12:34:43Gordon SpenceManual testing266267--2.163--
2018-05-23T12:04:31ramgeisManual testing267268--4.327--
2020-01-03T13:24:46mnd9Manual testing268269--8.654--
2020-12-21T22:42:35takahashiManual testing269270--17.31--
2021-08-10T15:26:09SRBaseManual testing270271--34.61--
2021-09-25T07:07:35SRBaseManual testing271272--69.23--


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)
1999-04-13T00:00:00ANONYMOUSv4_computers2B01297CE4DA4C__1.506
1999-06-26T00:00:00ANONYMOUSv4_computersC93FEDC52AECBACF1.506
2001-11-24T00:00:00Sturle Sundev4_computersC93FEDC52AECBACF1.506


PRP results:
No PRP results for M6908281


P-1 factor-bounds graph:
B1 = 4000000, B2 = 456818670 (P-1 stage 2)
B1 = 3000000, B2 = 75000000 (P-1 stage 2)
B1 = 4000000 (P-1 stage 1)
B1 = 3000000 (P-1 stage 1)
B1 = 405000, B2 = 12251250 (P-1 stage 2)
B1 = 405000 (P-1 stage 1)
B1 = 85000, B2 = 1487500 (P-1 stage 2)
B1 = 85000 (P-1 stage 1)
B1 = 35000, B2 = 437500 (P-1 stage 2)
B1 = 35000 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2021-11-30T02:54:15+00:00