is 2 848387 - 1
has 255390 decimal digits
takes 0.021 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L8688DF40F5B26ED2double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26735.024070.1493%114323625258886521.387610.6477%36.411673.3277%3.1784%
PrimeNet2400.000050.0000%80003200000.000922.8269%0.000961.4134%11.4134%
GPU722440.000054.5455%140005500000.001517.5652%0.001562.5296%7.9842%
Difference+23+35.0240+15.6038%+11418362+525338652+1.3860-6.9175%+36.4101+10.7980%+10.7980%

Known prime factors (1 factor, 113.2 bits, 0.01334057% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
8483871176160667774494125986170940874225735113.1806931746171113502010203898344
23 × 32 × 7 × 29 × 41 × 43 × 89 × 613 × 3739 × 7297 × 180722203
2014-08-1072971807222031.802e+110.34650.6466

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-01-08T00:00:00ANONYMOUSv4_computers2000200000---0.000--0.207%
2002-02-10T00:00:00ANONYMOUSv4_computers4096409600---0.001--0.441%
2002-04-14T00:00:00ANONYMOUSv4_computers8192819200---0.002--0.794%
2002-05-18T00:00:00ANONYMOUSv4_computers163841638400---0.004--1.288%
2002-06-23T00:00:00ANONYMOUSv4_computers327683276800---0.007--1.930%
2002-12-09T00:00:00ANONYMOUSv4_computers655376553700---0.015--2.711%
2003-08-08T00:00:00ANONYMOUSv4_computers13107213107200---0.029--3.621%
2009-08-30T00:19:00Carsten Kossendeyleela848387848387---0.030--2.217%
2012-03-20T00:28:00Jocelyn LaroucheManual testing12334911233491---0.043--2.563%
2013-10-28T06:35:00David Campeaui5-2500k125000040000000---0.118--6.110%
2014-08-10T14:52:00mikrMSI114323625258886521235113.1801.3880.0412.77510.648%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2000-08-10T00:00:00ANONYMOUSv4_computers21255--0.006--
2001-01-14T00:00:00ANONYMOUSv4_computers21256--0.011--
2001-11-24T00:00:00ANONYMOUSv4_computers21257--0.023--
2003-09-09T00:00:00ANONYMOUSv4_computers21258--0.045--
2008-10-18T00:52:00Sturle Sundeaalto.ifi258259--0.045--
2008-10-18T01:23:00Sturle Sundeaalto.ifi259260--0.091--
2010-05-27T19:30:00Architects Cubeda3_bu2260261--0.181--


ECM factoring results:

Old Calculation Method

Total ECM effort:13.981 GHz-days
Estimated T-Level:25.344
DigitsB1CurvesCompleteFacMiss
2011000325 / 1003.2503.815%
2550000325 / 2801.16131.261%
3025000044 / 6400.06993.351%

New Calculation Method

Total ECM effort:13.981 GHz-days
Estimated T-Level:25.344
DigitsB1CompleteFacMiss
201100012.7310.000%
25500001.34925.941%
302500000.10889.793%
3510000000.00799.295%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002817.842
25000025000000446.139


Lucas-Lehmer results:
No L-L results for M848387


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-28T04:09:33Oliver KruseGTX-2
11761606677744941259861709408742257
8C9A285E0015CE__no
2017-10-14T08:17:51Oliver KruseThreadripper8C9A285E0015CE__no
2017-12-18T09:55:46ATHxps
11761606677744941259861709408742257
8C9A285E0015CE__no
2020-04-21T23:48:36Oliver KruseAddPrpType5
11761606677744941259861709408742257
0C67265C79B67F__no


P-1 factor-bounds graph:
B1 = 11432362, B2 = 525888652 (P-1 stage 2)
B1 = 11432362 (P-1 stage 1)
B1 = 1250000, B2 = 40000000 (P-1 stage 2)
B1 = 1250000 (P-1 stage 1)
B1 = 1233491 (P-1 stage 1)
B1 = 848387 (P-1 stage 1)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 65537, B2 = 6553700 (P-1 stage 2)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 16384, B2 = 1638400 (P-1 stage 2)
B1 = 65537 (P-1 stage 1)
B1 = 8192, B2 = 819200 (P-1 stage 2)
B1 = 32768 (P-1 stage 1)
B1 = 4096, B2 = 409600 (P-1 stage 2)
B1 = 16384 (P-1 stage 1)
B1 = 2000, B2 = 200000 (P-1 stage 2)
B1 = 8192 (P-1 stage 1)
B1 = 4096 (P-1 stage 1)
B1 = 2000 (P-1 stage 1)
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TF factor-bounds graph:
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2100
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Last modified: 2020-04-21T23:48:36+00:00