is 2 2495551 - 1
has 751236 decimal digits
takes 0.173 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L99EDEB450B6AEB23double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26823.884567.6471%2382500857701000.69657.5526%24.581070.0905%2.4435%
PrimeNet2590.030862.7119%100001800000.00192.5370%0.032763.6579%0.9460%
GPU722630.639565.0794%110001600000.00191.3816%0.641565.5618%0.4825%
Difference+5+23.2449+2.5677%+2371500+85610100+0.6946+6.1710%+23.9395+4.5287%+4.5287%

Known prime factors (1 factor, 76.0 bits, 0.00304722% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2495551779457939233459837394712376.04515616950710152985
5 × 6791 × 459930811667
2021-04-13679145993081166712,1122,520.24,707.0

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-23T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.235%
2003-10-31T00:00:00Team Prime Ribv4_computers15000228750---0.003--0.786%
2010-12-22T11:37:00Jocelyn LaroucheManual testing2000020000---0.002--0.263%
2011-01-25T04:27:00Oscar Östlin950001971250---0.020--2.387%
2014-09-10T00:51:00Jocelyn LaroucheManual testing120719120719---0.012--0.917%
2014-12-08T09:34:00mikrMSI238250085770100---0.697--7.553%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-05-02T00:00:00ANONYMOUSv4_computers21259--0.031--
2016-02-23T16:29:15Mark RoseManual testing259260--0.031--
2009-01-11T10:25:00Sturle Sundeginglo.ifi260261--0.062--
2012-06-11T14:21:00Sebastian HornbostelManual testing261262--0.123--
2013-01-14T11:53:00dbaughManual testing262263--0.393--
2015-03-03T21:37:00VictordeHollanderManual testing263264--0.787--
2015-03-03T21:37:00VictordeHollanderManual testing264265--1.497--
2015-10-31T16:44:06ramgeisManual testing265266--2.994--
2017-07-24T22:21:29Gordon SpenceManual testing266267--5.989--
2019-03-25T14:11:01TJAOIManual testing267268--11.98--


ECM factoring results:

Old Calculation Method

Total ECM effort:10.754 GHz-days
Estimated T-Level:22.089
DigitsB1CurvesCompleteFacMiss
2011000117 / 1001.17030.854%
2550000117 / 2800.41865.796%

New Calculation Method

Total ECM effort:10.754 GHz-days
Estimated T-Level:22.089
DigitsB1CompleteFacMiss
20110003.7742.296%
25500000.34171.098%
302500000.02197.921%


ECM Summary

B1B2factorcurvesGHz-days
50000500000011510.57
50000500000020.184


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-06-15T00:00:00ANONYMOUSv4_computers99EDEB450B6AEB230.173
2018-06-01T13:12:36kkmrkkblmbrbkold99EDEB450B6AEB230.173


PRP results:
dateuseridcompidcofactorsres64PRP
2021-04-20T03:57:49NesowaLaptop
77945793923345983739471
8F7FFDB1F9392A__no
2021-04-21T03:37:58XZTN4640G1
77945793923345983739471
8F7FFDB1F9392A26no


P-1 factor-bounds graph:
B1 = 2382500, B2 = 85770100 (P-1 stage 2)
B1 = 2382500 (P-1 stage 1)
B1 = 95000, B2 = 1971250 (P-1 stage 2)
B1 = 120719 (P-1 stage 1)
B1 = 95000 (P-1 stage 1)
B1 = 15000, B2 = 228750 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
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105
106
107
102
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109
1010
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1012
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
259
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260
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2100
Last modified: 2021-04-21T03:37:58+00:00