is 2 2571181 - 1
has 774003 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-LAD9B8617FF064BB5double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26823.181967.6471%32000001120000000.91808.0794%24.099970.2610%2.6139%
PrimeNet2590.029962.7119%110002000000.00212.6894%0.032063.7147%1.0028%
GPU722630.620765.0794%120001900000.00221.5043%0.622965.6047%0.5253%
Difference+5+22.5612+2.5677%+3188000+111810000+0.9158+6.5751%+23.4770+4.6563%+4.6563%

Known prime factors (1 factor, 79.3 bits, 0.00308241% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
25711817209665190492488421538072479.254140201432541942563
11 × 12745584776540233
2020-07-02111274558477654023389,90669,839,786130,441,271

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-31T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.237%
2003-11-08T00:00:00Team Prime Ribv4_computers15000202500---0.003--0.761%
2010-12-21T01:10:00Jocelyn LaroucheManual testing2000020000---0.002--0.265%
2011-01-10T23:58:00Jocelyn LaroucheManual testing5000050000---0.005--0.532%
2011-04-16T14:53:00James HeinrichWHS1750004112500---0.039--3.173%
2016-06-12T08:06:14mikrMSI320000011200000012---0.918--8.079%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-26T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:16Mark RoseManual testing259260--0.030--
2009-01-30T02:17:00Sturle Sundescarpia.ifi260261--0.060--
2012-06-18T20:43:00Sebastian HornbostelManual testing261262--0.119--
2013-01-14T11:55:00dbaughManual testing262263--0.382--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.764--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.453--
2015-11-08T21:03:04ramgeisManual testing265266--2.906--
2017-08-13T10:39:21Gordon SpenceManual testing266267--5.813--
2019-09-06T09:38:24YxinityManual testing267268--11.63--


ECM factoring results:

Old Calculation Method

Total ECM effort:3.508 GHz-days
Estimated T-Level:1.900
DigitsB1CurvesCompleteFacMiss
201100038 / 1000.38068.255%
255000038 / 2800.13687.288%

New Calculation Method

Total ECM effort:3.508 GHz-days
Estimated T-Level:1.900
DigitsB1CompleteFacMiss
20110001.22629.352%
25500000.11189.513%
302500000.00799.320%


ECM Summary

B1B2factorcurvesGHz-days
500005000000363.324
50000500000020.185


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-05-02T00:00:00ANONYMOUSv4_computersAD9B8617FF064BB50.178
2018-06-16T19:58:10kkmrkkblmbrbkoldAD9B8617FF064BB50.178


PRP results:
dateuseridcompidcofactorsres64PRP
2020-07-02T14:52:50mrh.orgw
720966519049248842153807
68AFF281FF3BAC03no
2020-07-03T11:34:15nordisweet16
720966519049248842153807
68AFF281FF3BAC03no


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 175000, B2 = 4112500 (P-1 stage 2)
B1 = 175000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 15000, B2 = 202500 (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)
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TF factor-bounds graph:
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Last modified: 2020-07-03T11:34:15+00:00