is 2 4872877 - 1
has 1466883 decimal digits
takes 0.675 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LCC579ABBC16A23B0double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual2676.097865.6716 %3200002243412602.51748.0992 %8.615268.4520 %
Target2651.497264.6154 %3200035000000.04442.3718 %1.541665.4546 %
Difference+2+4.6006+1.0563 %+288000+220841260+2.4730+5.7274%+7.0736+2.9973 %

Known prime factors (1 factor, 76.6 bits, 0.00157095% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
48728771106686804559355623904712476.55111355579102031055
5 × 653 × 340117 × 10225811
2013-12-21340117102258113,694.70.17660.2091

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2009-08-17Carsten Kossendeymother30000435000--0.0102.064%
2013-12-21David Campeaui5-2500k2476.5510.1990.000%
2023-04-13Kevin_9611Factor_2320000224341260--2.8689.659%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2010-04-19markroldgamer2612620.063
2011-10-09GrunwalderGIMPManual testing212630.327


ECM factoring results:
Total ECM effort:0.395 GHz-days
Estimated T-Level:0.577
DigitsB1CompleteFacMiss
20110000.11589.102%
25500000.01198.938%


ECM Summary

B1B2factorcurvesGHz-days
50000500000030.395


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-06-14ANONYMOUSv4_computersCC579ABBC16A23B00.675
2000-03-27Charlie Dorianv4_computersCC579ABBC16A23B00.675


PRP results:
dateuseridcompidcofactorsres64
2017-09-20kkmrkkblmbrbkManual testing
110668680455935562390471
33011A8AD2BEBEC2
2018-04-01ATHec2-PRPCFDC
110668680455935562390471
33011A8AD2BEBEC2


CERT results:
No CERT results for M4872877


P-1 factor-bounds graph:
B1 = 320000, B2 = 224341260 (P-1 stage 2)
B1 = 320000 (P-1 stage 1)
B1 = 30000, B2 = 435000 (P-1 stage 2)
B1 = 30000 (P-1 stage 1)
103
104
105
106
103
104
105
106
107
108
109
TF factor-bounds graph:
263
262
this exponent TF target: 65
TF double-checked to: 67
ECM T-Level=0.58 ~= -15-bit
250
260
270
280
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Last modified: 2024-03-13T02:15:48+00:00