is 2 2216281 - 1
has 667168 decimal digits
takes 0.146 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L9B237B676F964F17double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26713.407167.1642 %500000150000000.12305.1866 %13.530168.8673 %
Target2620.277264.5161 %110009000000.00571.6294 %0.282965.0943 %
Difference+5+13.1299+2.6481 %+489000+14100000+0.1173+3.5573%+13.2472+3.7730 %

Known prime factors (2 factors, 152.2 bits, 0.00686929% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2216281260219906367939881668092374.4625870643351811884
22 × 33 × 41 × 347 × 3820749899
2022-11-0334738207498991,726.319.84637.067
22162812595837078275680808801032477.78158562905116176171
41 × 311 × 694781 × 6610441
2015-11-16694781661044113,8110.09700.1348

1 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-03-16ANONYMOUSv4_computers204820480012--0.0010.781%
2010-10-11Oscar Östlin7501175011--0.0071.594%
2010-12-19Oscar Östlin8500015937506--0.0164.396%
2014-05-26JossManual testing113960113960--0.0111.963%
2014-09-29JossManual testing142920142920--0.0142.181%
2015-04-28Squeeky_SquirrelP4_260016000046000006--0.0385.948%
2015-11-16Alexander DubrovinManual testing100000070000001222477.7810.1277.552%
2016-04-24alpertronManual testing5000001500000012---8.278%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-02-07ANONYMOUSv4_computers212580.017
2022-03-09LordJuliusManual testing21260
2009-01-10Sturle Sundefigaro.ifi2602610.069
2012-04-18Sebastian HornbostelManual testing2612620.139
2013-01-23dbaughManual testing2622630.443
2015-03-06VictordeHollanderManual testing2632640.886
2015-03-06VictordeHollanderManual testing2642651.686
2015-10-23ramgeisManual testing2652663.372


ECM factoring results:
Total ECM effort:7.786 GHz-days
Estimated T-Level:21.531
DigitsB1CompleteFacMiss
20110003.2493.883%
25500000.30673.617%
302500000.01998.074%


ECM Summary

B1B2factorcurvesGHz-days
500005000000151.146
500006356363504.764
50000640000070.669
50000700000070.699
500002702353520.509


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-15ANONYMOUSv4_computers9B237B676F964F170.146


PRP results:
dateuseridcompidcofactorsres64
2017-09-30alpertronManual testing
259583707827568080880103
0D7CB0E341AE2940
2017-10-26Oliver KruseGTX-3
259583707827568080880103
0D7CB0E341AE2940
2022-11-05NesowaLaptop
259583707827568080880103
26021990636793988166809
7AB026138A32FDCB


CERT results:
dateuseridcompid
2022-11-05gregor_krannichC2E92EF9B


P-1 factor-bounds graph:
B1 = 1000000, B2 = 7000000 (P-1 stage 2)
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 500000 (P-1 stage 1)
B1 = 160000, B2 = 4600000 (P-1 stage 2)
B1 = 85000, B2 = 1593750 (P-1 stage 2)
B1 = 160000 (P-1 stage 1)
B1 = 142920 (P-1 stage 1)
B1 = 113960 (P-1 stage 1)
B1 = 85000 (P-1 stage 1)
B1 = 75011 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
266
265
264
263
262
261
260
258
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=21.53 ~= 55-bit
250
260
270
280
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Last modified: 2024-02-29T14:28:04+00:00