is 2 2758531 - 1
has 830401 decimal digits
takes 0.213 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L8A733B64E9E33033double-checked
PRP169BD06AF77185D4verified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26821.607567.6471%2700000840000000.79847.6790%22.405970.1315%2.4844%
PrimeNet2590.027862.7119%120002200000.00262.8541%0.030563.7761%1.0642%
GPU722630.578665.0794%150002400000.00311.7449%0.581665.6887%0.6093%
Difference+5+21.0289+2.5677%+2685000+83760000+0.7954+5.9342%+21.8243+4.4428%+4.4428%

Known prime factors (1 factor, 92.5 bits, 0.00335325% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
275853170046955760660247861365727692892.5001269642352408949688464
24 × 16262303 × 4879545475543
2020-12-05162623034879545475543489,823,34729,77555,608

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2000-03-22T00:00:00ANONYMOUSv4_computers15000153750---0.003--0.706%
2002-01-02T00:00:00ANONYMOUSv4_computers20000240000---0.004--0.903%
2002-01-02T00:00:00ANONYMOUSv4_computers500001500000---0.014--1.961%
2003-11-16T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.242%
2014-04-16T21:18:00Jocelyn LaroucheManual testing6000060000---0.007--0.609%
2014-04-22T10:35:00Jocelyn LaroucheManual testing100000100000---0.011--0.838%
2014-10-19T12:31:00Jocelyn LaroucheManual testing123268123268---0.014--0.945%
2015-05-08T04:15:00Squeeky_SquirrelP4_26001950006045000---0.058--3.539%
2017-01-03T20:36:24mikrMSI27000008400000012---0.798--7.679%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-04-11T00:00:00netconxv4_computers21259--0.028--
2016-02-23T16:29:21Mark RoseManual testing259260--0.028--
2009-01-31T09:24:00Sturle Sundegoose.ifi260261--0.056--
2012-03-21T21:17:00markroldgamer261262--0.111--
2013-01-14T12:31:00dbaughManual testing262263--0.356--
2015-04-21T09:20:00VictordeHollanderManual testing263264--0.712--
2015-04-21T09:20:00VictordeHollanderManual testing264265--1.354--
2016-02-05T15:45:59ramgeisManual testing265266--2.709--
2017-10-09T09:26:13Gordon SpenceManual testing266267--5.418--
2019-02-21T01:08:07chuenkitManual testing267268--10.84--


ECM factoring results:

Old Calculation Method

Total ECM effort:6.548 GHz-days
Estimated T-Level:3.150
DigitsB1CurvesCompleteFacMiss
201100063 / 1000.63053.091%
255000063 / 2800.22579.819%

New Calculation Method

Total ECM effort:6.548 GHz-days
Estimated T-Level:3.150
DigitsB1CompleteFacMiss
20110002.4238.865%
25500000.22479.916%
302500000.01498.596%


ECM Summary

B1B2factorcurvesGHz-days
500005000000575.924
50000500000060.624


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-04-27T00:00:00netconxv4_computers8A733B64E9E330330.213
1999-08-31T00:00:00ANONYMOUSv4_computers6850E70167D7D5__0.213
2000-03-27T00:00:00ANONYMOUSv4_computers8A733B64E9E330330.213
2018-08-16T09:34:55kkmrkkblmbrbkold8A733B64E9E330330.213


PRP results:
dateuseridcompidcofactorsres64PRP
2020-12-05T13:03:52SRJ2877LTOS
7004695576066024786136572769
169BD06AF77185D4no


P-1 factor-bounds graph:
B1 = 2700000, B2 = 84000000 (P-1 stage 2)
B1 = 2700000 (P-1 stage 1)
B1 = 195000, B2 = 6045000 (P-1 stage 2)
B1 = 195000 (P-1 stage 1)
B1 = 50000, B2 = 1500000 (P-1 stage 2)
B1 = 123268 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 60000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 20000, B2 = 240000 (P-1 stage 2)
B1 = 15000, B2 = 153750 (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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104
105
106
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108
102
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109
1010
1011
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1013
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: 2020-12-05T13:03:52+00:00