is 2 2686267 - 1
has 808647 decimal digits
takes 0.207 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L523B7E5E72931BC0double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26822.188767.6471%2000000500000000.51696.8677%22.705669.8690%2.2219%
PrimeNet2590.028662.7119%120002200000.00262.8404%0.031263.7710%1.0591%
GPU722630.594165.0794%130002200000.00271.6230%0.596965.6461%0.5668%
Difference+5+21.5946+2.5677%+1987000+49780000+0.5141+5.2447%+22.1087+4.2228%+4.2228%

Known prime factors (1 factor, 81.3 bits, 0.00302552% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
268626729226672077926227597387612581.274544001621542576140
22 × 3 × 5 × 17 × 64237 × 8302612561
2020-08-06642378302612561243,86950.66694.618

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-11-08T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.240%
2003-11-28T00:00:00Team Prime Ribv4_computers15000217500---0.003--0.786%
2010-12-22T11:37:00Jocelyn LaroucheManual testing2000020000---0.002--0.268%
2010-12-26T02:29:00Jocelyn LaroucheManual testing3000030000---0.003--0.371%
2011-02-02T12:35:00markrtiny1050002283750---0.025--2.550%
2016-06-17T04:08:31Jocelyn LaroucheManual testing16750045675006---0.046--3.242%
2016-12-21T00:33:40Jocelyn Larouchelow 4M201000201000---0.023--1.224%
2017-04-13T02:13:58Jocelyn Larouchelow 4M33500033500006---0.056--3.342%
2018-07-09T21:12:19Jocelyn Larouchelow 4M67000067000006---0.112--4.223%
2019-11-17T15:45:16masserManual testing20000005000000012---0.517--6.868%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2016-02-23T16:29:19Mark RoseManual testing21260--0.057--
2009-02-01T02:39:00Sturle Sundegerle.ifi260261--0.057--
2012-05-07T23:13:00markroldgamer261262--0.114--
2013-01-14T12:26:00dbaughManual testing262263--0.365--
2015-02-23T17:25:00VictordeHollanderManual testing263264--0.731--
2015-02-23T17:25:00VictordeHollanderManual testing264265--1.391--
2016-01-26T10:48:53ramgeisManual testing265266--2.782--
2017-09-13T08:55:34Gordon SpenceManual testing266267--5.564--
2019-04-29T13:20:16TJAOIManual testing267268--11.13--


ECM factoring results:

Old Calculation Method

Total ECM effort:4.347 GHz-days
Estimated T-Level:2.100
DigitsB1CurvesCompleteFacMiss
201100042 / 1000.42065.566%
255000042 / 2800.15086.048%

New Calculation Method

Total ECM effort:4.347 GHz-days
Estimated T-Level:2.100
DigitsB1CompleteFacMiss
20110001.35525.799%
25500000.12288.475%
302500000.00899.249%


ECM Summary

B1B2factorcurvesGHz-days
500005000000394.036
50000500000030.310


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-04-23T00:00:00ANONYMOUSv4_computers523B7E5E72931BC00.207


PRP results:
dateuseridcompidcofactorsres64PRP
2020-08-07T02:41:31CrypticCluecruncher
2922667207792622759738761
371713ED2186489Cno
2020-08-08T00:56:37LOBESGoogleCloud
2922667207792622759738761
371713ED2186489Cno


P-1 factor-bounds graph:
B1 = 2000000, B2 = 50000000 (P-1 stage 2)
B1 = 2000000 (P-1 stage 1)
B1 = 670000, B2 = 6700000 (P-1 stage 2)
B1 = 670000 (P-1 stage 1)
B1 = 335000, B2 = 3350000 (P-1 stage 2)
B1 = 167500, B2 = 4567500 (P-1 stage 2)
B1 = 335000 (P-1 stage 1)
B1 = 105000, B2 = 2283750 (P-1 stage 2)
B1 = 201000 (P-1 stage 1)
B1 = 167500 (P-1 stage 1)
B1 = 105000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 217500 (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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102
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1010
TF factor-bounds graph:
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265
264
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2100
Last modified: 2020-08-08T00:56:37+00:00