is 2 2747551 - 1
has 827096 decimal digits
takes 0.212 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L22DE15AE68B02F83double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26821.693867.6471 %2700000840000000.79847.6760 %22.492370.1305 %
Target2630.580965.0794 %1400012000000.00881.7088 %0.589765.6761 %
Difference+5+21.1129+2.5677 %+2686000+82800000+0.7896+5.9672%+21.9026+4.4544 %

Known prime factors (1 factor, 74.6 bits, 0.00271665% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2747551294610797705289885256812374.6415361334470320840
23 × 5 × 11 × 12184851068911
2020-10-2211121848510689111,392.574,348138,861

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-11-16ANONYMOUSv4_computers2048204800--0.0010.678%
2003-11-28Team Prime Ribv4_computers15000225000--0.0031.712%
2010-12-21JossManual testing2000020000--0.0020.635%
2010-12-30JossManual testing3000030000--0.0040.839%
2011-01-21JossManual testing5000050000--0.0061.150%
2011-05-03James HeinrichWHS19000046550006--0.0495.648%
2016-11-26mikrMSI27000008400000012--0.77811.366%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-01-26ANONYMOUSv4_computers212590.014
2016-02-23Mark RoseManual testing2592600.028
2009-01-27Sturle Sundeinteravia.ifi2602610.056
2012-04-06Grant McCrackenthumper2612620.112
2013-01-14dbaughManual testing2622630.357
2015-04-21VictordeHollanderManual testing2632640.715
2015-04-21VictordeHollanderManual testing2642651.360
2016-02-04ramgeisManual testing2652662.720
2017-10-09Gordon SpenceManual testing2662675.440
2019-02-19chuenkitManual testing26726810.88


ECM factoring results:
Total ECM effort:5.495 GHz-days
Estimated T-Level:20.979
DigitsB1CompleteFacMiss
20110002.11512.059%
25500000.19682.223%
302500000.01298.773%


ECM Summary

B1B2factorcurvesGHz-days
500005000000504.976
50000500000050.519


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-01-26ANONYMOUSv4_computers22DE15AE68B02F830.212
1999-06-15dlsilverv4_computers22DE15AE68B02F830.212
2018-08-14kkmrkkblmbrbkold22DE15AE68B02F830.207


PRP results:
dateuseridcompidcofactorsres64
2020-10-22mrhp
29461079770528988525681
CC5593A86E8B56AD


CERT results:
dateuseridcompid
2020-10-22ahbanksD820


P-1 factor-bounds graph:
B1 = 2700000, B2 = 84000000 (P-1 stage 2)
B1 = 2700000 (P-1 stage 1)
B1 = 190000, B2 = 4655000 (P-1 stage 2)
B1 = 190000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 225000 (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)
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1010
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TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
259
this exponent TF target: 63
TF double-checked to: 67
ECM T-Level=20.98 ~= 53-bit
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Last modified: 2024-02-09T03:30:02+00:00