is 2 2528651 - 1
has 761200 decimal digits
takes 0.175 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LC1399A24174C933Fdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26823.571867.6471%30000001350000001.02508.2579%24.596870.3187%2.6717%
PrimeNet2590.030462.7119%110001900000.00212.6446%0.032563.6980%0.9861%
GPU722630.631265.0794%110001800000.00201.4348%0.633265.5804%0.5011%
Difference+5+22.9406+2.5677%+2989000+134820000+1.0230+6.8231%+23.9636+4.7383%+4.7383%

Known prime factors (1 factor, 75.1 bits, 0.00297019% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2528651406485629793438427553772375.1068037598501996488
23 × 32 × 3533 × 31597314613
2020-06-123533315973146133,254.0173.14323.37

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-23T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.236%
2003-10-31T00:00:00Team Prime Ribv4_computers15000236250---0.003--0.796%
2010-12-19T21:42:00Jocelyn LaroucheManual testing2000020000---0.002--0.264%
2011-01-02T14:09:00Jocelyn LaroucheManual testing3000030000---0.003--0.366%
2011-01-06T23:25:00Jocelyn LaroucheManual testing5000050000---0.005--0.530%
2011-03-17T05:57:00James HeinrichWHS3000008000000---0.072--3.956%
2017-12-16T19:44:43Jocelyn Larouchelow 4M60000060000006---0.090--4.045%
2018-06-26T08:45:00mikrMSI300000013500000012---1.025--8.258%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.030--
1999-04-13T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:16Mark RoseManual testing259260--0.030--
2009-01-31T07:43:00Sturle Sundegehry.ifi260261--0.061--
2012-06-14T07:43:00Sebastian HornbostelManual testing261262--0.121--
2013-01-23T08:30:00dbaughManual testing262263--0.388--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.776--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.478--
2015-11-08T21:03:09ramgeisManual testing265266--2.955--
2017-08-08T13:42:07Gordon SpenceManual testing266267--5.910--
2019-04-15T13:43:02TJAOIManual testing267268--11.82--


ECM factoring results:

Old Calculation Method

Total ECM effort:3.407 GHz-days
Estimated T-Level:1.850
DigitsB1CurvesCompleteFacMiss
201100037 / 1000.37068.945%
255000037 / 2800.13287.601%

New Calculation Method

Total ECM effort:3.407 GHz-days
Estimated T-Level:1.850
DigitsB1CompleteFacMiss
20110001.19430.314%
25500000.10889.774%
302500000.00799.338%


ECM Summary

B1B2factorcurvesGHz-days
500005000000363.315
50000500000010.092


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-26T00:00:00ANONYMOUSv4_computersC1399A24174C933F0.175
1999-04-13T00:00:00ANONYMOUSv4_computersC1399A24174C933F0.175
2018-06-07T12:47:20kkmrkkblmbrbkoldC1399A24174C933F0.175


PRP results:
dateuseridcompidcofactorsres64PRP
2020-06-13T16:33:04CrypticCluecruncher
40648562979343842755377
4B4D4A6851E9F7B2no
2020-06-13T17:08:27ATHec2-PRPCFDC
40648562979343842755377
4B4D4A6851E9F7B2no


P-1 factor-bounds graph:
B1 = 3000000, B2 = 135000000 (P-1 stage 2)
B1 = 3000000 (P-1 stage 1)
B1 = 600000, B2 = 6000000 (P-1 stage 2)
B1 = 300000, B2 = 8000000 (P-1 stage 2)
B1 = 600000 (P-1 stage 1)
B1 = 300000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 236250 (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
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107
102
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104
105
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1010
1011
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
259
250
260
270
280
290
2100
Last modified: 2020-06-13T17:08:27+00:00