is 2 268637 - 1
has 80868 decimal digits
takes 0.002 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L5C3A4C0AF6AED15Bdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual267110.609971.6418%2425000679000000.05946.2867%110.669373.4246%1.7828%
PrimeNet2400.000052.5000%2800800000.000114.8172%0.000159.5382%7.0382%
GPU722440.000056.8182%50001200000.000110.6039%0.000161.3971%4.5790%
Difference+23+110.6099+14.8236%+2420000+67780000+0.0593-4.3172%+110.6692+12.0274%+12.0274%

Known prime factors (1 factor, 85.3 bits, 0.03175169% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
268637475218877120831835789872792685.29788450004489484292147
163 × 2467 × 572683 × 384084529
2015-11-1257268338408452952,699,0000.21270.3873

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-03-25T00:00:00ANONYMOUSv4_computers1000004000000---0.003--2.269%
2001-06-23T00:00:00ANONYMOUSv4_computers10000010000000---0.006--2.741%
2002-06-02T00:00:00ANONYMOUSv4_computers327683276800---0.002--1.573%
2002-08-10T00:00:00ANONYMOUSv4_computers655366553600---0.004--2.259%
2003-03-16T00:00:00ANONYMOUSv4_computers13107213107200---0.008--3.074%
2003-11-16T00:00:00ANONYMOUSv4_computers26214426214400---0.017--4.005%
2006-01-15T00:00:00Jocelyn Larouchev4_computers268637268637---0.003--1.099%
2011-02-16T23:34:00Jocelyn LaroucheManual testing20000002000000---0.020--2.626%
2012-02-26T15:18:00Jocelyn LaroucheManual testing22828822282882---0.023--2.753%
2013-10-14T23:39:00David Campeaui5-2500k242500067900000---0.059--6.287%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-24T00:00:00ANONYMOUSv4_computers252253--0.002--
2000-04-27T00:00:00ANONYMOUSv4_computers21254--0.009--
2022-03-07T05:52:50LordJuliusManual testing254255--0.009--
2001-02-25T00:00:00ANONYMOUSv4_computers21256--0.036--
2002-03-31T00:00:00ANONYMOUSv4_computers21257--0.071--
2022-03-07T05:52:50LordJuliusManual testing257258--0.071--
2008-12-31T22:59:00Sturle Sunderodolfo.ifi258259--0.143--
2009-01-24T14:21:00Sturle Sundegibsy.ifi259260--0.286--
2013-07-06T22:20:00lycornasteroid260261--0.572--
2015-08-25T13:23:00NRManual testing261262--1.143--


ECM factoring results:

Old Calculation Method

Total ECM effort:10.005 GHz-days
Estimated T-Level:26.672
DigitsB1CurvesCompleteFacMiss
2011000496 / 1004.9600.684%
2550000496 / 2801.77116.955%
30250000214 / 6400.33471.560%

New Calculation Method

Total ECM effort:10.005 GHz-days
Estimated T-Level:26.672
DigitsB1CompleteFacMiss
201100026.9300.000%
25500003.4243.259%
302500000.33271.777%
3510000000.02697.461%
4030000000.00299.835%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002822.058
250000250000001916.970
2500002500000020.073
2500003825000070.301
25000038500000140.603


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2001-11-10T00:00:00ANONYMOUSv4_computers5C3A4C0AF6AED15B0.002


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-22T09:42:27Oliver KruseDoppelherz
47521887712083183578987279
FD30CEA115B990__no
2017-09-22T10:03:17Oliver KruseManual testing
47521887712083183578987279
FD30CEA115B990__no
2017-09-30T15:30:09alpertronManual testing
47521887712083183578987279
FD30CEA115B990__no
2017-12-07T05:01:51ATHxps
47521887712083183578987279
FD30CEA115B990__no
2020-04-17T21:13:55Oliver KruseAddPrpType5
47521887712083183578987279
09B561BE30CDED__no


P-1 factor-bounds graph:
B1 = 2425000, B2 = 67900000 (P-1 stage 2)
B1 = 2425000 (P-1 stage 1)
B1 = 2282882 (P-1 stage 1)
B1 = 2000000 (P-1 stage 1)
B1 = 262144, B2 = 26214400 (P-1 stage 2)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 100000, B2 = 10000000 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 100000, B2 = 4000000 (P-1 stage 2)
B1 = 268637 (P-1 stage 1)
B1 = 262144 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 65536 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-04-08T00:01:32+00:00