is 2 8620639 - 1
has 2595071 decimal digits
takes 2.251 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L158C287618FE85ECdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual2686.914264.7059%10000018500000.07402.8646%6.988265.7169%1.0110%
PrimeNet2640.412962.5000%3600010000000.03353.3041%0.446463.7390%1.2390%
GPU722686.914264.7059%5500012000000.04442.2936%6.958665.5154%0.8095%
Difference---+45000+650000+0.0295+0.5711%+0.0295+0.2016%+0.2016%

Known prime factors (1 factor, 69.8 bits, 0.00080974% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
862063910312425366457311202732269.80559812418583224
23 × 19 × 61 × 97 × 66503761
2019-10-10976650376124.2481.37192.5622

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-02-02T00:00:00ANONYMOUSv4_computers45000618750---0.029--1.848%
2003-04-19T00:00:00Team Prime Ribv4_computers40000260000---0.020--1.389%
2012-01-15T05:47:00bcp19Manual testing1000001850000---0.074--2.865%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-10-18T00:00:00ANONYMOUSv4_computers21261--0.036--
1998-11-14T00:00:00Roger Kohnv4_computers21263--0.185--
1999-10-15T00:00:00ANONYMOUSv4_computers21264--0.413--
2014-01-26T14:23:00lycornManual testing264265--0.433--
2015-05-25T09:34:00VictordeHollanderManual testing265266--0.867--
2016-02-03T20:13:16snme2pm1Manual testing266267--1.734--
2018-04-25T15:00:11monstManual testing267268--3.467--


ECM factoring results:

Old Calculation Method

Total ECM effort:2.382 GHz-days
Estimated T-Level:0.300
DigitsB1CurvesCompleteFacMiss
20110006 / 1000.06094.148%
25500006 / 2800.02197.876%

New Calculation Method

Total ECM effort:2.382 GHz-days
Estimated T-Level:0.300
DigitsB1CompleteFacMiss
20110000.23179.392%
25500000.02197.887%
302500000.00199.865%


ECM Summary

B1B2factorcurvesGHz-days
50000500000031.191
50000500000031.191


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-12-08T00:00:00ANONYMOUSv4_computers158C287618FE85EC2.251
2003-02-27T00:00:00ANONYMOUSv4_computers158C287618FE85EC2.251
2003-04-19T00:00:00Team Prime Ribv4_computers0B755C02423455__2.251


PRP results:
dateuseridcompidcofactorsres64PRP
2019-10-11T11:43:24mnd975211backdoorb
1031242536645731120273
C77FF6BECEAA2408no
2019-10-12T13:48:18theSpirit83i7-7700HQ
1031242536645731120273
C77FF6BECEAA2408no


P-1 factor-bounds graph:
B1 = 100000, B2 = 1850000 (P-1 stage 2)
B1 = 100000 (P-1 stage 1)
B1 = 45000, B2 = 618750 (P-1 stage 2)
B1 = 40000, B2 = 260000 (P-1 stage 2)
B1 = 45000 (P-1 stage 1)
B1 = 40000 (P-1 stage 1)
100
101
102
103
104
105
100
101
102
103
104
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106
107
108
TF factor-bounds graph:
268
267
266
265
264
263
261
250
260
270
280
290
2100
Last modified: 2019-10-12T13:48:18+00:00