is 2 2655251 - 1
has 799311 decimal digits
takes 0.205 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L078CD2FFDAB492D8double-checked
PRPDBEB9ADC44ED3FF2verified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual272360.166969.4444%2000000500000000.51694.8396%360.683870.9232%1.4788%
PrimeNet2590.028962.7119%110002000000.00242.7053%0.031363.7206%1.0088%
GPU722630.601165.0794%130002000000.00261.5754%0.603765.6295%0.5501%
Difference+9+359.5659+4.3651%+1987000+49800000+0.5143+3.2642%+360.0801+5.2937%+5.2937%

Known prime factors (1 factor, 92.2 bits, 0.00347193% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
265525156425826816055380510914007772892.1881062532822999697213388
22 × 3 × 7 × 149 × 2659 × 2901323 × 11004299
2021-01-29290132311004299597,503,8720.37440.6613

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-31T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.099%
2009-06-23T13:38:00harleeP4_260030000420000---0.006--0.673%
2011-01-16T22:49:00James Heinrichi7-9201800004320000---0.045--2.061%
2016-12-24T22:38:24Jocelyn Larouchelow 4M143325143325---0.016--0.586%
2016-12-26T22:14:23Jocelyn Larouchelow 4M171990171990---0.019--0.654%
2016-12-28T03:20:08Jocelyn Larouchelow 4M206388206388---0.023--0.727%
2017-05-08T05:55:52Jocelyn Larouchelow 4M36000036000006---0.060--2.228%
2019-11-30T16:25:46masserManual testing20000005000000012---0.517--4.840%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-01-13T00:00:00ANONYMOUSv4_computers21259--0.029--
2016-02-23T16:29:18Mark RoseManual testing259260--0.029--
2009-01-27T05:31:00Sturle Sundegollumilla.ifi260261--0.058--
2012-05-28T15:19:00markroldgamer261262--0.116--
2012-07-15T17:18:00dbaughManual testing262263--0.370--
2012-07-16T06:01:00dbaughManual testing263264--0.739--
2012-07-18T07:13:00dbaughManual testing264265--1.407--
2012-07-18T07:17:00dbaughManual testing265266--2.814--
2012-07-23T04:49:00dbaughManual testing266267--5.629--
2012-07-23T07:04:00dbaughManual testing267268--11.26--
2012-07-28T11:18:00dbaughManual testing268269--22.51--
2012-09-05T18:17:00dbaughManual testing269270--45.03--
2012-11-04T10:42:00dbaughManual testing270271--90.06--
2013-01-27T10:09:00dbaughManual testing271272--180.1--


ECM factoring results:

Old Calculation Method

Total ECM effort:8.471 GHz-days
Estimated T-Level:4.100
DigitsB1CurvesCompleteFacMiss
201100082 / 1000.82043.862%
255000082 / 2800.29374.574%

New Calculation Method

Total ECM effort:8.471 GHz-days
Estimated T-Level:4.100
DigitsB1CompleteFacMiss
20110002.6457.099%
25500000.23978.736%
302500000.01598.539%


ECM Summary

B1B2factorcurvesGHz-days
500005000000818.368
50000500000010.103


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-03-03T00:00:00ANONYMOUSv4_computers078CD2FFDAB492D80.205
1999-09-14T00:00:00ANONYMOUSv4_computers078CD2FFDAB492D80.205
2018-07-20T08:54:00kkmrkkblmbrbkold078CD2FFDAB492D80.205


PRP results:
dateuseridcompidcofactorsres64PRP
2021-01-29T12:54:16ViliamF3
5642582681605538051091400777
DBEB9ADC44ED3FF2no


P-1 factor-bounds graph:
B1 = 2000000, B2 = 50000000 (P-1 stage 2)
B1 = 2000000 (P-1 stage 1)
B1 = 360000, B2 = 3600000 (P-1 stage 2)
B1 = 180000, B2 = 4320000 (P-1 stage 2)
B1 = 360000 (P-1 stage 1)
B1 = 206388 (P-1 stage 1)
B1 = 180000 (P-1 stage 1)
B1 = 171990 (P-1 stage 1)
B1 = 143325 (P-1 stage 1)
B1 = 30000, B2 = 420000 (P-1 stage 2)
B1 = 30000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
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108
TF factor-bounds graph:
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Last modified: 2021-01-29T12:54:16+00:00