is 2 2131361 - 1
has 641604 decimal digits
takes 0.140 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LCD4836F5EBBCBF29double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26827.965667.6471%25000001250000000.87467.9100%28.840370.2062%2.5591%
PrimeNet2580.018062.0690%90001700000.00172.7293%0.019763.1042%1.0352%
GPU722620.288264.5161%100001500000.00171.4863%0.289965.0435%0.5274%
Difference+6+27.6774+3.1309%+2490000+124850000+0.8730+6.4237%+28.5504+5.1627%+5.1627%

Known prime factors (1 factor, 73.1 bits, 0.00343139% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2131361103730653983618542385772373.1352433436991284408
23 × 19 × 71287 × 224577467
2020-07-18712872245774671,322.61.17292.1787

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2011-01-12T23:59:00Jocelyn LaroucheManual testing5000050000---0.005--0.512%
2011-01-22T08:25:00James Heinrichi7-9201400003045000---0.028--2.779%
2016-06-29T03:46:57Jocelyn LaroucheManual testing210000609000012---0.051--3.464%
2017-08-19T15:19:16Jocelyn Larouchelow 4M42000042000006---0.060--3.511%
2017-08-30T00:32:09Jocelyn Larouchelow 4M50400050400006---0.072--3.737%
2017-09-24T02:12:39mikrMSI250000012500000012---0.875--7.910%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1997-11-12T00:00:00ANONYMOUSv4_computers21257--0.009--
1999-01-29T00:00:00ANONYMOUSv4_computers21258--0.018--
2016-02-23T16:29:06Mark RoseManual testing258260--0.054--
2009-01-05T05:08:00Sturle Sundecelair.ifi260261--0.072--
2012-04-14T21:49:00Sebastian HornbostelManual testing261262--0.144--
2013-09-07T11:35:00ramgeisManual testing262263--0.461--
2015-03-15T12:13:00VictordeHollanderManual testing263264--0.921--
2015-03-15T12:13:00VictordeHollanderManual testing264265--1.753--
2015-12-27T16:49:12ramgeisManual testing265266--3.506--
2016-10-29T15:24:08Gordon SpenceManual testing266267--7.012--
2019-04-29T13:20:35TJAOIManual testing267268--14.02--


ECM factoring results:

Old Calculation Method

Total ECM effort:8.526 GHz-days
Estimated T-Level:21.786
DigitsB1CurvesCompleteFacMiss
2011000100 / 1001.00036.603%
2550000100 / 2800.35769.923%

New Calculation Method

Total ECM effort:8.526 GHz-days
Estimated T-Level:21.786
DigitsB1CompleteFacMiss
20110003.2263.972%
25500000.29274.711%
302500000.01898.221%


ECM Summary

B1B2factorcurvesGHz-days
500005000000998.440
50000500000010.085


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1997-11-12T00:00:00ANONYMOUSv4_computersCD4836F5EBBCBF290.140
1999-02-07T00:00:00ANONYMOUSv4_computersCD4836F5EBBCBF290.140
2018-04-05T19:32:56kkmrkkblmbrbkoldCD4836F5EBBCBF290.140


PRP results:
dateuseridcompidcofactorsres64PRP
2020-07-17T18:21:12ATHec2-PRPCF
10373065398361854238577
AA225866B94DD4A9no
2020-07-17T20:19:20oodairacom2
10373065398361854238577
AA225866B94DD4A9no


P-1 factor-bounds graph:
B1 = 2500000, B2 = 125000000 (P-1 stage 2)
B1 = 2500000 (P-1 stage 1)
B1 = 504000, B2 = 5040000 (P-1 stage 2)
B1 = 420000, B2 = 4200000 (P-1 stage 2)
B1 = 210000, B2 = 6090000 (P-1 stage 2)
B1 = 504000 (P-1 stage 1)
B1 = 420000 (P-1 stage 1)
B1 = 140000, B2 = 3045000 (P-1 stage 2)
B1 = 210000 (P-1 stage 1)
B1 = 140000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
103
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106
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103
104
105
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109
TF factor-bounds graph:
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Last modified: 2020-07-18T00:11:59+00:00