is 2 1544021 - 1
has 464797 decimal digits
takes 0.069 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L259142041FFD672Ddouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26719.244568.6567 %500000150000000.08354.9657 %19.328170.2131 %
Target2610.198965.5738 %65003000000.00151.0480 %0.200465.9346 %
Difference+6+19.0456+3.0829 %+493500+14700000+0.0821+3.9177%+19.1276+4.2786 %

Known prime factors (2 factors, 133.5 bits, 0.00864676% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1544021395064473785216729032065.09912793364655831
32 × 1421484961759
2008-03-01914214849617594.72515,015.99,368.4
15440213919043177954913032872168.409126910293899983
11 × 157 × 2113 × 34778033
2019-06-2121133477803338.6040.12280.2292

1 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-09-29Team Prime Ribv4_computers20000290000--0.0022.368%
2016-03-17alpertronManual testing5000001500000012---8.703%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-10-18Stephen Woodv4_computers212570.012
2003-08-08ANONYMOUSv4_computers212580.025


ECM factoring results:
Total ECM effort:30.113 GHz-days
Estimated T-Level:25.701
DigitsB1CompleteFacMiss
201100014.5380.000%
25500001.64019.395%
302500000.14086.925%
3510000000.01099.024%


ECM Summary

B1B2factorcurvesGHz-days
10.127
50000500000021211.84
500005000000362.011
250000350000005016.13


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-11-07Stephen Woodv4_computers259142041FFD672D0.069


PRP results:
dateuseridcompidcofactorsres64
2017-10-01Oliver KruseGTX-2
39506447378521672903
C8A02086305FF2F3
2017-10-30kkmrkkblmbrbkold
39506447378521672903
C8A02086305FF2F3
2019-06-21ATHec2-PRPCF
39506447378521672903
391904317795491303287
9E4DDE6BBE2E0C70
2019-06-22kkmrkkblmbrbkc5.large
39506447378521672903
391904317795491303287
9E4DDE6BBE2E0C70


CERT results:
No CERT results for M1544021


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
B1 = 20000, B2 = 290000 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
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103
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106
100
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1010
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TF factor-bounds graph:
258
257
this exponent TF target: 61
TF double-checked to: 67
ECM T-Level=25.7 ~= 69-bit
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Last modified: 2024-02-29T14:28:04+00:00