is 2 21791897 - 1
has 6560015 decimal digits
takes 15.443 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LAAC5D66FA7EBD83Cdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual274175.563766.2162 %800000424890003.15614.4806 %178.719767.7299 %
Target2695.478563.7681 %160000225000001.41513.8417 %6.893665.1600 %
Difference+5+170.0852+2.4481 %+640000+19989000+1.7409+0.6388%+171.8261+2.5699 %

Known prime factors (1 factor, 78.9 bits, 0.00036190% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
217918975500547693611139664977032478.86412620626129086283
7 × 11 × 97 × 311 × 1019 × 5331923
2022-01-23101953319235,571.50.29950.5575

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2004-01-07ANONYMOUSv4_computers2100001470000--0.2863.078%
2022-01-23bayanneBasta8000004248900022478.8643.2477.058%


Trial Factoring results:
575859606162636465666768697071727374
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2003-01-25S04803v4_computers212670.686
2017-05-01ramgeisManual testing2672681.372
2017-12-04VictordeHollanderManual testing2682692.743
2018-05-03ramgeisManual testing2692705.487
2021-09-06TheJudgerManual testing27027376.81
2021-10-02TheJudgerManual testing27327487.79


ECM factoring results:
No ECM results for M21791897


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2004-04-29ANONYMOUSv4_computersAAC5D66FA7EBD83C15.44
2009-02-20Hairy BearfishywishyAAC5D66FA7EBD83C17.68


PRP results:
No PRP results for M21791897


CERT results:
No CERT results for M21791897


P-1 factor-bounds graph:
B1 = 800000, B2 = 42489000 (P-1 stage 2)
B1 = 800000 (P-1 stage 1)
B1 = 210000, B2 = 1470000 (P-1 stage 2)
B1 = 210000 (P-1 stage 1)
102
103
104
105
106
102
103
104
105
106
107
108
TF factor-bounds graph:
274
273
270
269
268
267
this exponent TF target: 69
TF double-checked to: 67
250
260
270
280
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Last modified: 2024-03-13T02:15:48+00:00