is 2 2255797 - 1
has 679063 decimal digits
takes 0.148 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LDC9AABCC4D1F3725double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26826.423067.6471%1000000200000000.19405.3765%26.617069.3865%1.7395%
PrimeNet2580.017062.0690%100001900000.00192.9176%0.018963.1756%1.1067%
GPU722620.272364.5161%120001900000.00211.7056%0.274465.1214%0.6052%
Difference+6+26.1506+3.1309%+988000+19810000+0.1920+3.6709%+26.3426+4.2652%+4.2652%

Known prime factors (1 factor, 78.8 bits, 0.00349306% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
22557975249164035047111737064892478.796116348324672989452
22 × 3 × 131 × 5182157 × 14282263
2020-07-2151821571428226344,1250.54131.0055

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-04-03T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.228%
2010-11-06T12:26:00Jocelyn LaroucheManual testing1500015000---0.001--0.200%
2010-11-12T11:43:00Jocelyn LaroucheManual testing3000030000---0.003--0.357%
2011-01-06T01:30:00markrtiny1000002075000---0.020--2.404%
2014-09-02T00:10:00Jocelyn LaroucheManual testing128453128453---0.012--0.933%
2016-03-02T12:01:16Jocelyn LaroucheManual testing342144615859212---0.063--3.758%
2019-06-28T03:46:10BigBrotherWinston10000002000000012---0.194--5.377%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2016-02-23T16:29:10Mark RoseManual testing21260--0.068--
2009-01-11T04:10:00Sturle Sundedietrich.ifi260261--0.068--
2012-05-04T16:48:00Sebastian HornbostelManual testing261262--0.136--
2013-01-23T08:24:00dbaughManual testing262263--0.435--
2015-03-10T10:44:00VictordeHollanderManual testing263264--0.870--
2015-03-10T10:44:00VictordeHollanderManual testing264265--1.656--
2015-10-29T11:36:23ramgeisManual testing265266--3.313--
2017-01-05T21:20:50Gordon SpenceManual testing266267--6.625--
2019-05-13T13:38:17TJAOIManual testing267268--13.25--


ECM factoring results:

Old Calculation Method

Total ECM effort:7.473 GHz-days
Estimated T-Level:4.350
DigitsB1CurvesCompleteFacMiss
201100087 / 1000.87041.712%
255000087 / 2800.31173.252%

New Calculation Method

Total ECM effort:7.473 GHz-days
Estimated T-Level:4.350
DigitsB1CompleteFacMiss
20110002.8066.042%
25500000.25477.597%
302500000.01698.450%


ECM Summary

B1B2factorcurvesGHz-days
500005000000847.215
50000500000030.258


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-01T00:00:00ANONYMOUSv4_computersDC9AABCC4D1F37250.148
2018-04-23T16:34:21kkmrkkblmbrbkoldDC9AABCC4D1F37250.148


PRP results:
dateuseridcompidcofactorsres64PRP
2020-07-21T21:04:26CrypticClueManual testing
524916403504711173706489
449DBE1759F5A56Ano
2020-07-24T20:39:13oodairacom1
524916403504711173706489
449DBE1759F5A56Ano


P-1 factor-bounds graph:
B1 = 1000000, B2 = 20000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 342144, B2 = 6158592 (P-1 stage 2)
B1 = 342144 (P-1 stage 1)
B1 = 100000, B2 = 2075000 (P-1 stage 2)
B1 = 128453 (P-1 stage 1)
B1 = 100000 (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
103
104
105
106
107
102
103
104
105
106
107
108
TF factor-bounds graph:
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267
266
265
264
263
262
261
260
250
260
270
280
290
2100
Last modified: 2020-07-24T20:39:13+00:00