is 2 2158679 - 1
has 649828 decimal digits
takes 0.142 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26713.764967.1642 %500000150000000.12305.1703 %13.887868.8619 %
Target2620.284664.5161 %100008000000.00511.5190 %0.289765.0551 %
Difference+5+13.4803+2.6481 %+490000+14200000+0.1179+3.6512%+13.5982+3.8067 %

Known prime factors (1 factor, 32.5 bits, 0.00150445% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
215867959752234731032.4761384
23 × 173
-81733.445e-101.620e-61.710e-6

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2016-03-31alpertronManual testing5000001500000012
skipped known factor: 5975223473
---8.254%


Trial Factoring results:
5758596061626364656667
No TF results for M2158679


ECM factoring results:
Total ECM effort:15.844 GHz-days
Estimated T-Level:21.918
DigitsB1CompleteFacMiss
20110004.0291.779%
25500000.38468.144%
302500000.02597.568%
3510000000.00199.883%


ECM Summary

B1B2factorcurvesGHz-days
500005000000171.452
50000690000070.691
50000696710070.694
50000702535170.697
50000270235355012.31


Lucas-Lehmer results:
No L-L results for M2158679


PRP results:
dateuseridcompidcofactorsres64
2017-10-09Oliver KruseGTX-2
5975223473
1554F0F61375EA30
2017-11-18kkmrkkblmbrbkc4.xlarge
5975223473
1554F0F61375EA30


CERT results:
No CERT results for M2158679


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
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101
102
103
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105
106
100
101
102
103
104
105
106
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108
TF factor-bounds graph:
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=21.92 ~= 56-bit
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Last modified: 2024-03-13T02:15:48+00:00