is 2 21801877 - 1
has 6563019 decimal digits
takes 15.451 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
Actual2671.362962.6866 %----1.362962.6866 %
Target2695.476063.7681 %160000225000001.41513.8419 %6.891165.1601 %
Difference-2-4.1131-1.0815 %-160000-22500000-1.4151-3.8419 %-5.5282-2.4736 %

Known prime factors (3 factors, 142.8 bits, 0.00065490% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
21801877654056311929.28515
3 × 5
2011-06-24353.291e-123.195e-66.274e-6
218018773696564058155131548.3938477628
22 × 3 × 17 × 29 × 1433
2011-06-242914333.413e-60.00010.0002
21801877396005414402006620012065.102908191103000
23 × 53 × 908191103
2018-06-051259081911030.616650.84694.966

4 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2011-06-24AxonManual testing2477.6780.9410.000%


Trial Factoring results:
57585960616263646566676869
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2018-06-05TJAOIManual testing265266*
65.102
20
0.035


ECM factoring results:
No ECM results for M21801877


Lucas-Lehmer results:
No L-L results for M21801877


PRP results:
No PRP results for M21801877


CERT results:
No CERT results for M21801877


P-1 factor-bounds graph:
100
101
102
103
100
101
102
103
104
105
106
107
108
109
TF factor-bounds graph:
this exponent TF target: 69
TF double-checked to: 67
250
260
270
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Last modified: 2024-03-13T02:15:48+00:00