is 2 2581837 - 1
has 777211 decimal digits
takes 0.179 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LE22C83722F05EF52double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26823.086267.6471%32000001120000000.91808.0827%24.004270.2620%2.6150%
PrimeNet2590.029762.7119%110002000000.00212.6914%0.031963.7154%1.0036%
GPU722630.618265.0794%120001900000.00221.5055%0.620465.6051%0.5257%
Difference+5+22.4681+2.5677%+3188000+111810000+0.9158+6.5772%+23.3839+4.6569%+4.6569%

Known prime factors (1 factor, 69.7 bits, 0.00269969% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
25818379599996156998459821372169.702185914063455564
22 × 3 × 313 × 49497886969		2020-08-073134949788696950.692271.23506.57

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_computers15000206250---0.003--0.767%
2010-11-14T20:17:00Jocelyn LaroucheManual testing2000020000---0.002--0.266%
2011-01-12T23:59:00Jocelyn LaroucheManual testing5000050000---0.005--0.532%
2011-10-10T14:04:00markrtiny1750004112500---0.039--3.175%
2016-07-21T19:53:46mikrMSI320000011200000012---0.918--8.083%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-26T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:17Mark RoseManual testing259260--0.030--
2009-01-31T02:13:00Sturle Sundekinner.ifi260261--0.059--
2012-06-20T17:43:00Sebastian HornbostelManual testing261262--0.119--
2013-01-14T11:55:00dbaughManual testing262263--0.380--
2015-02-27T20:35:00VictordeHollanderManual testing263264--0.760--
2015-02-27T20:35:00VictordeHollanderManual testing264265--1.447--
2015-11-08T21:03:07ramgeisManual testing265266--2.894--
2017-08-20T12:59:34Gordon SpenceManual testing266267--5.789--
2019-06-29T11:41:21lycornManual testing267268--11.58--


ECM factoring results:

Old Calculation Method

Total ECM effort:4.988 GHz-days
Estimated T-Level:2.700
DigitsB1CurvesCompleteFacMiss
201100054 / 1000.54058.117%
255000054 / 2800.19382.432%

New Calculation Method

Total ECM effort:4.988 GHz-days
Estimated T-Level:2.700
DigitsB1CompleteFacMiss
20110001.74217.518%
25500000.15785.433%
302500000.01099.035%


ECM Summary

B1B2factorcurvesGHz-days
500005000000514.711
50000500000030.277


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-05-02T00:00:00ANONYMOUSv4_computersE22C83722F05EF520.179
2018-06-19T07:56:15kkmrkkblmbrbkoldE22C83722F05EF520.179


PRP results:
dateuseridcompidcofactorsres64PRP
2020-08-07T19:18:39pew10980xe_1
959999615699845982137
05CB9BC99024C8E5no
2020-08-08T06:59:57marssystemsSYSTEM01
959999615699845982137
05CB9BC99024C8E5no


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 = 206250 (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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101
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1010
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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: 2020-08-08T06:59:57+00:00