is 2 2560697 - 1
has 770847 decimal digits
takes 0.178 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L6BEEA137C81B026Ddouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26823.276867.6471%32000001120000000.91808.0762%24.194870.2599%2.6129%
PrimeNet2590.030062.7119%110002000000.00212.6873%0.032163.7139%1.0021%
GPU722630.623365.0794%120001800000.00211.4793%0.625465.5959%0.5166%
Difference+5+22.6535+2.5677%+3188000+111820000+0.9159+6.5969%+23.5694+4.6640%+4.6640%

Known prime factors (1 factor, 71.8 bits, 0.00280278% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
256069740286163726245673865272271.771786624964340679
32 × 73 × 4373 × 273793339
2020-07-314373273793339314.401.50072.8021

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-23T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.237%
2003-11-08T00:00:00Team Prime Ribv4_computers15000198750---0.003--0.756%
2010-12-21T01:09:00Jocelyn LaroucheManual testing2000020000---0.002--0.265%
2011-01-03T14:36:00Jocelyn LaroucheManual testing3000030000---0.003--0.367%
2011-01-10T23:57:00Jocelyn LaroucheManual testing5000050000---0.005--0.531%
2011-04-12T01:58:00James HeinrichWHS1750004068750---0.039--3.164%
2016-04-26T10:16:52mikrMSI320000011200000012---0.918--8.076%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-05-23T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:16Mark RoseManual testing259260--0.030--
2009-01-31T06:34:00Sturle Sundegouffy.ifi260261--0.060--
2012-06-16T20:43:00Sebastian HornbostelManual testing261262--0.120--
2013-01-14T11:55:00dbaughManual testing262263--0.383--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.767--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.459--
2015-11-08T21:03:00ramgeisManual testing265266--2.918--
2017-08-11T09:15:23Gordon SpenceManual testing266267--5.836--
2019-07-01T11:10:59TJAOIManual testing267268--11.67--


ECM factoring results:

Old Calculation Method

Total ECM effort:4.890 GHz-days
Estimated T-Level:2.650
DigitsB1CurvesCompleteFacMiss
201100053 / 1000.53058.704%
255000053 / 2800.18982.727%

New Calculation Method

Total ECM effort:4.890 GHz-days
Estimated T-Level:2.650
DigitsB1CompleteFacMiss
20110001.71018.092%
25500000.15585.683%
302500000.01099.053%


ECM Summary

B1B2factorcurvesGHz-days
500005000000514.705
50000500000020.185


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-11-04T00:00:00ANONYMOUSv4_computers6BEEA137C81B026D0.178
2018-06-13T21:34:09kkmrkkblmbrbkold6BEEA137C81B026D0.178


PRP results:
dateuseridcompidcofactorsres64PRP
2020-08-02T09:31:36ANONYMOUSdory
4028616372624567386527
CCD9408D77F77A4Ano
2020-08-05T11:08:00fre_gamesgpu
4028616372624567386527
CCD9408D77F77A4Ano


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 175000, B2 = 4068750 (P-1 stage 2)
B1 = 175000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 198750 (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
103
104
105
106
107
102
103
104
105
106
107
108
109
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
259
250
260
270
280
290
2100
Last modified: 2020-08-05T11:08:00+00:00