is 2 2157427 - 1
has 649451 decimal digits
takes 0.142 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LFFADA30BBA442D06double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26827.627867.6471%50000002000000001.48968.9408%29.117370.5397%2.8926%
PrimeNet2580.017862.0690%100001700000.00182.8096%0.019663.1347%1.0657%
GPU722620.284864.5161%100001600000.00171.5189%0.286565.0551%0.5390%
Difference+6+27.3430+3.1309%+4990000+199840000+1.4878+7.4219%+28.8308+5.4846%+5.4846%

Known prime factors (1 factor, 71.6 bits, 0.00331667% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
215742734685241297117613179292271.555803856661131932
22 × 156127 × 1287183929
2020-04-301561271287183929433.296.700012.488

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-03-07T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.225%
2010-11-04T10:39:00Jocelyn LaroucheManual testing1500015000---0.001--0.198%
2010-11-07T01:16:00Jocelyn LaroucheManual testing3000030000---0.003--0.353%
2010-11-07T12:40:00Jocelyn LaroucheManual testing4500045000---0.004--0.477%
2010-11-10T11:27:00Jocelyn LaroucheManual testing6000060000---0.006--0.580%
2011-01-23T19:35:00markrtiny1200002340000---0.023--2.546%
2014-10-03T21:04:00Jocelyn LaroucheManual testing149750149750---0.014--1.008%
2016-04-16T18:12:07Jocelyn LaroucheManual testing240000884234412---0.068--3.822%
2017-09-05T23:15:06Jocelyn Larouchelow 4M48000048000006---0.068--3.682%
2017-09-13T23:12:02Jocelyn Larouchelow 4M57600057600006---0.082--3.913%
2019-09-29T15:11:17mikrMSI500000020000000012---1.490--8.941%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-01-29T00:00:00ANONYMOUSv4_computers21258--0.018--
2016-02-23T16:29:07Mark RoseManual testing258260--0.053--
2009-01-05T02:20:00Sturle Sundejodel.ifi260261--0.071--
2009-01-07T18:56:00Sturle Sundemorovan.ifi261262--0.142--
2013-09-08T17:50:00ramgeisManual testing262263--0.455--
2015-03-22T08:28:00VictordeHollanderManual testing263264--0.910--
2015-03-22T08:28:00VictordeHollanderManual testing264265--1.732--
2015-12-30T18:01:35ramgeisManual testing265266--3.464--
2016-11-04T03:09:03Gordon SpenceManual testing266267--6.927--
2019-05-13T13:38:19TJAOIManual testing267268--13.85--


ECM factoring results:

Old Calculation Method

Total ECM effort:6.575 GHz-days
Estimated T-Level:3.850
DigitsB1CurvesCompleteFacMiss
201100077 / 1000.77046.122%
255000077 / 2800.27575.920%

New Calculation Method

Total ECM effort:6.575 GHz-days
Estimated T-Level:3.850
DigitsB1CompleteFacMiss
20110002.4848.342%
25500000.22479.892%
302500000.01498.627%


ECM Summary

B1B2factorcurvesGHz-days
500005000000756.404
50000500000020.171


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-15T00:00:00ANONYMOUSv4_computersFFADA30BBA442D060.142
2018-04-10T05:13:37kkmrkkblmbrbkoldFFADA30BBA442D060.142


PRP results:
dateuseridcompidcofactorsres64PRP
2020-04-30T14:53:58ATHec2-PRPCF
3468524129711761317929
F6B9FCBCA70D1130no
2020-05-02T13:30:38Luigi Morelli9800X
3468524129711761317929
F6B9FCBCA70D1130no


P-1 factor-bounds graph:
B1 = 5000000, B2 = 200000000 (P-1 stage 2)
B1 = 5000000 (P-1 stage 1)
B1 = 576000, B2 = 5760000 (P-1 stage 2)
B1 = 480000, B2 = 4800000 (P-1 stage 2)
B1 = 240000, B2 = 8842344 (P-1 stage 2)
B1 = 576000 (P-1 stage 1)
B1 = 480000 (P-1 stage 1)
B1 = 120000, B2 = 2340000 (P-1 stage 2)
B1 = 240000 (P-1 stage 1)
B1 = 149750 (P-1 stage 1)
B1 = 120000 (P-1 stage 1)
B1 = 60000 (P-1 stage 1)
B1 = 45000 (P-1 stage 1)
B1 = 30000 (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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102
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104
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1010
TF factor-bounds graph:
268
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266
265
264
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261
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Last modified: 2020-05-02T13:30:38+00:00