is 2 56128621 - 1
has 16896399 decimal digits
takes 118.961 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
Actual2692.127062.3188 %----2.127062.3188 %
Target27334.079764.3836 %4000006500000012.04574.0606 %46.125365.8298 %
Difference-4-31.9526-2.0647 %-400000-65000000-12.0457-4.0606 %-43.9983-3.5110 %

Known prime factors (1 factor, 69.0 bits, 0.00012295% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
561286215948875022050128580012169.0115299324049000
23 × 53 × 113 × 389 × 120557
2011-06-033891205573.07680.02130.0377

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2011-06-03David CampeauManual testing2169.0112.4590.000%


Trial Factoring results:
5758596061626364656667686970717273
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-12-08ANONYMOUSv4_computers212532.14000e-5
2000-03-01ANONYMOUSv4_computers212544.28000e-5
2000-05-31ANONYMOUSv4_computers212560.000
2001-09-16ANONYMOUSv4_computers212570.000
2002-09-14ANONYMOUSv4_computers212580.001
2004-10-031997rj7v4_computers212600.001
2022-06-15LordJuliusManual testing260263
2008-06-23David Campeau2632640.033
2008-06-24Sturle Sundedoak.ifi2642670.466
2009-11-18Sturle Sundegibsy.ifi2672680.533
2011-04-12GrunwalderGIMPcompute-0-02682691.065


ECM factoring results:
No ECM results for M56128621


Lucas-Lehmer results:
No L-L results for M56128621


PRP results:
No PRP results for M56128621


CERT results:
No CERT results for M56128621


P-1 factor-bounds graph:
101
102
103
101
102
103
104
105
106
TF factor-bounds graph:
269
268
267
264
263
260
258
257
256
254
253
this exponent TF target: 73
TF double-checked to: 67
250
260
270
280
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Last modified: 2024-03-13T02:15:48+00:00