is 2 1953587 - 1
has 588089 decimal digits
takes 0.106 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L1A1A8C16837E1E9Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26830.510569.1176%19535872441983751.19198.4447%31.702471.7256%2.6079%
PrimeNet2580.019763.7931%80001400000.00122.4676%0.020864.6866%0.8935%
GPU722620.314566.1290%8000900000.00101.1536%0.315566.5198%0.3907%
Difference+6+30.1960+2.9886%+1945587+244108375+1.1909+7.2912%+31.3869+5.2058%+5.2058%

Known prime factors (1 factor, 87.0 bits, 0.00445243% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
19535871528269264689646259676051692786.98239114440889749119432
23 × 3566687 × 1370825393767
2020-08-183566687137082539376714,571,3745,875.310,973

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2011-05-16T18:46:00kurlyhex100000030000000---0.203--5.697%
2018-01-19T13:04:08Jocelyn Larouchelow 4M19535873000000012---0.274--6.051%
2018-02-12T21:00:12Jocelyn Larouchelow 4M19535876000000012---0.402--6.835%
2018-03-03T03:57:56Jocelyn Larouchelow 4M195358712000000012---0.660--7.627%
2018-05-11T11:44:16Jocelyn Larouchelow 4M195358719535870012---0.983--8.187%
2018-11-26T12:54:02Jocelyn LaroucheManual testing195358724419837512---1.192--8.445%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-12-21T00:00:00ANONYMOUSv4_computers21258--0.020--
2016-02-23T16:29:00Mark RoseManual testing258260--0.059--
2010-01-16T23:03:00S485122USB-W260261--0.079--
2016-02-23T16:29:00Mark RoseManual testing261262--0.157--
2011-08-27T22:19:00GrunwalderGIMPManual testing21263--0.817--
2016-02-23T16:29:00Mark RoseManual testing262263--0.502--
2015-04-22T20:23:00lycornManual testing263264--1.005--
2015-04-22T20:23:00lycornManual testing264265--1.913--
2015-09-07T08:31:00ramgeisManual testing265266--3.825--
2018-02-05T16:30:32TJAOIManual testing266267--7.650--
2019-05-13T04:32:11chuenkitManual testing267268--15.30--


ECM factoring results:

Old Calculation Method

Total ECM effort:18.980 GHz-days
Estimated T-Level:24.482
DigitsB1CurvesCompleteFacMiss
2011000251 / 1002.5108.025%
2550000251 / 2800.89640.737%

New Calculation Method

Total ECM effort:18.980 GHz-days
Estimated T-Level:24.482
DigitsB1CompleteFacMiss
20110008.4700.021%
25500000.75946.828%
302500000.04795.420%
3510000000.00299.785%


ECM Summary

B1B2factorcurvesGHz-days
5000050000001389.60
50000500000050.348
5000075000001089.029


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-17T00:00:00ANONYMOUSv4_computers1A1A8C16837E1E9E0.106
2015-07-10T01:00:00MadPooManual testing1A1A8C16837E1E9E0.106


PRP results:
dateuseridcompidcofactorsres64PRP
2020-08-21T09:00:46Sébastien BrouckePortable_Seb
152826926468964625967605169
0F72EDFB714FAC4Dno
2020-08-22T08:27:54marssystemssystem03
152826926468964625967605169
0F72EDFB714FAC4Dno


P-1 factor-bounds graph:
B1 = 1953587, B2 = 244198375 (P-1 stage 2)
B1 = 1953587, B2 = 195358700 (P-1 stage 2)
B1 = 1953587, B2 = 120000000 (P-1 stage 2)
B1 = 1953587, B2 = 60000000 (P-1 stage 2)
B1 = 1953587, B2 = 30000000 (P-1 stage 2)
B1 = 1000000, B2 = 30000000 (P-1 stage 2)
B1 = 1953587 (P-1 stage 1)
B1 = 1000000 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-05-12T09:18:05+00:00