is 2 2495551 - 1
has 751236 decimal digits
takes 0.173 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L99EDEB450B6AEB23double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26823.884567.6471 %2382500857701000.69657.5526 %24.581070.0905 %
Target2630.639565.0794 %110008000000.00541.3816 %0.645065.5618 %
Difference+5+23.2449+2.5677 %+2371500+84970100+0.6911+6.1710%+23.9360+4.5287 %

Known prime factors (1 factor, 76.0 bits, 0.00304722% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2495551779457939233459837394712376.04515616950710152985
5 × 6791 × 459930811667
2021-04-13679145993081166712,1122,520.24,707.0

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-10-23ANONYMOUSv4_computers2048204800--0.0010.661%
2003-10-31Team Prime Ribv4_computers15000228750--0.0031.688%
2010-12-22JossManual testing2000020000--0.0020.622%
2011-01-25Oscar Östlin9500019712506--0.0204.257%
2014-09-10JossManual testing120719120719--0.0121.805%
2014-12-08mikrMSI23825008577010012--0.69711.227%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-05-02ANONYMOUSv4_computers212590.015
2016-02-23Mark RoseManual testing2592600.031
2009-01-11Sturle Sundeginglo.ifi2602610.062
2012-06-11Sebastian HornbostelManual testing2612620.123
2013-01-14dbaughManual testing2622630.393
2015-03-03VictordeHollanderManual testing2632652.284
2015-10-31ramgeisManual testing2652662.994
2017-07-24Gordon SpenceManual testing2662675.989
2019-03-25TJAOIManual testing26726811.98


ECM factoring results:
Total ECM effort:10.598 GHz-days
Estimated T-Level:22.082
DigitsB1CompleteFacMiss
20110004.5001.111%
25500000.41665.944%
302500000.02697.408%
3510000000.00199.877%


ECM Summary

B1B2factorcurvesGHz-days
50000500000011510.41
50000500000020.184


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-06-15ANONYMOUSv4_computers99EDEB450B6AEB230.173
2018-06-01kkmrkkblmbrbkold99EDEB450B6AEB230.173


PRP results:
dateuseridcompidcofactorsres64
2021-04-20NesowaLaptop
77945793923345983739471
8F7FFDB1F9392A26
2021-04-21XZTN4640G1
77945793923345983739471
8F7FFDB1F9392A26


CERT results:
dateuseridcompid
2021-04-21curtiscwcm220a-17l


P-1 factor-bounds graph:
B1 = 2382500, B2 = 85770100 (P-1 stage 2)
B1 = 2382500 (P-1 stage 1)
B1 = 95000, B2 = 1971250 (P-1 stage 2)
B1 = 120719 (P-1 stage 1)
B1 = 95000 (P-1 stage 1)
B1 = 15000, B2 = 228750 (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
103
104
105
106
107
102
103
104
105
106
107
108
109
1010
1011
1012
TF factor-bounds graph:
268
267
266
265
263
262
261
260
259
this exponent TF target: 63
TF double-checked to: 67
ECM T-Level=22.08 ~= 57-bit
250
260
270
280
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Last modified: 2024-03-13T02:15:48+00:00