is 2 66863851 - 1
has 20128025 decimal digits
takes 169.017 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
1 primality tests remaining
ResidueStatus
L-LD398EF1784375A__
needs double-check
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual276228.882965.7895%600000111000004.29603.1502%233.178966.8672%1.0777%
PrimeNet2703.573762.8571%280000130000003.56645.3176%7.140164.8322%1.9751%
GPU7227457.218764.8649%450000150000004.55493.9274%61.773766.2448%1.3799%
Difference+2+171.6642+0.9246%+150000-3900000-0.2590-0.7771%+171.4052+0.6224%+0.6224%

Known prime factors:
No known factors for M66863851

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2013-10-04T17:10:00Youcef Lseeler60000011100000---4.296--3.150%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2009-05-10T23:40:001997rj7Manual testing21264--0.053--
2010-02-05T07:27:00Hocapro2000264265--0.056--
2010-02-06T20:01:00Sturle Sundetumbili.ifi265266--0.112--
2010-02-09T17:30:00Donna Nobleq8200v2266267--0.224--
2010-02-14T17:42:00ITSWUV267268--0.447--
2010-02-19T18:33:00ITSWUV268269--0.894--
2012-07-27T15:08:00kdgehmanManual testing269270--1.788--
2013-04-05T02:47:00Brian V.Manual testing270271--3.576--
2013-04-05T02:47:00Brian V.Manual testing271272--7.153--
2013-09-18T22:40:00Jerry HallettManual testing272273--14.31--
2013-09-26T22:42:00Jerry HallettManual testing273274--28.61--
2021-07-19T01:03:53AyczlyManual testing274275--57.22--
2021-07-19T01:03:53AyczlyManual testing275276--114.4--


ECM factoring results:
No ECM results for M66863851


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2014-12-15T19:33:00alkochal-canariasD398EF1784375A__169.0


PRP results:
No PRP results for M66863851


P-1 factor-bounds graph:
B1 = 600000, B2 = 11100000 (P-1 stage 2)
B1 = 600000 (P-1 stage 1)
104
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104
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108
TF factor-bounds graph:
276
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274
273
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2100
Last modified: 2021-07-19T01:03:53+00:00