is 2 2421907 - 1
has 729067 decimal digits
takes 0.164 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L4C431E51C088743Ddouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual27098.662268.5714%2569240695240000.60906.1855%99.271270.5155%1.9440%
PrimeNet2590.031762.7119%100001800000.00192.5228%0.033663.6526%0.9407%
GPU722630.659065.0794%100001400000.00171.2772%0.660765.5254%0.4460%
Difference+7+98.0032+3.4921%+2559240+69384000+0.6073+4.9083%+98.6105+4.9901%+4.9901%

Known prime factors (1 factor, 74.1 bits, 0.00305823% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2421907197939494095157019694492374.0674086438787599132
22 × 3 × 43 × 7919455014727
2021-01-074379194550147272,199.342,26578,940

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-08T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.151%
2010-11-12T13:40:00Oscar Östlin7501175011---0.007--0.509%
2011-01-23T08:29:00Oscar Östlin950001923750---0.019--1.851%
2014-04-13T00:31:00mikrMSI256924069524000---0.609--6.186%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.032--
2016-02-23T16:29:14Mark RoseManual testing259260--0.032--
2009-01-14T20:47:00Sturle Sundegolan.ifi260261--0.063--
2012-06-04T21:42:00Sebastian HornbostelManual testing261262--0.127--
2013-12-04T21:13:00Jerry HallettManual testing262263--0.405--
2015-02-27T20:40:00VictordeHollanderManual testing263264--0.811--
2015-02-27T20:40:00VictordeHollanderManual testing264265--1.543--
2015-10-23T09:34:50ramgeisManual testing265266--3.085--
2017-07-05T06:34:29Gordon SpenceManual testing266267--6.171--
2019-04-29T13:20:24TJAOIManual testing267268--12.34--
2020-12-27T01:59:38Anton RepkoManual testing268270--74.05--


ECM factoring results:

Old Calculation Method

Total ECM effort:9.270 GHz-days
Estimated T-Level:21.857
DigitsB1CurvesCompleteFacMiss
2011000104 / 1001.04035.161%
2550000104 / 2800.37168.929%

New Calculation Method

Total ECM effort:9.270 GHz-days
Estimated T-Level:21.857
DigitsB1CompleteFacMiss
20110003.3553.492%
25500000.30373.845%
302500000.01998.150%


ECM Summary

B1B2factorcurvesGHz-days
5000050000001039.180
50000500000010.089


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-26T00:00:00ANONYMOUSv4_computers4C431E51C088743D0.164
2018-05-20T06:41:53kkmrkkblmbrbkold4C431E51C088743D0.164


PRP results:
dateuseridcompidcofactorsres64PRP
2021-01-07T05:55:16mrhw
19793949409515701969449
508AA0E754636EC3no
2021-01-07T20:27:09Lisander Viaene
19793949409515701969449
508AA0E754636EC3no


P-1 factor-bounds graph:
B1 = 2569240, B2 = 69524000 (P-1 stage 2)
B1 = 2569240 (P-1 stage 1)
B1 = 95000, B2 = 1923750 (P-1 stage 2)
B1 = 95000 (P-1 stage 1)
B1 = 75011 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2021-01-07T20:27:09+00:00