is 2 1603531 - 1
has 482711 decimal digits
takes 0.072 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L6727A7C75451165Adouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26718.530368.6567 %500000150000000.08354.9885 %18.613970.2203 %
Target2610.191665.5738 %65003000000.00151.0569 %0.193065.9376 %
Difference+6+18.3387+3.0829 %+493500+14700000+0.0821+3.9316%+18.4208+4.2827 %

Known prime factors (1 factor, 75.6 bits, 0.00471390% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1603531568214513169849301150632375.58917717603001434001
32 × 41 × 569 × 839 × 100578319
2008-03-288391005783194,771.90.35500.6629

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2016-03-17alpertronManual testing5000001500000012---8.739%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-10-29ANONYMOUSv4_computers212570.012
2003-05-04ANONYMOUSv4_computers212580.024


ECM factoring results:
Total ECM effort:31.356 GHz-days
Estimated T-Level:25.717
DigitsB1CompleteFacMiss
201100014.6150.000%
25500001.67118.807%
302500000.14386.643%
3510000000.01099.006%


ECM Summary

B1B2factorcurvesGHz-days
10.042
50000500000025014.02
250000400000005017.29


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-11-07ANONYMOUSv4_computers6727A7C75451165A0.072


PRP results:
dateuseridcompidcofactorsres64
2017-10-02Oliver KruseGTX-2
56821451316984930115063
37247659D3D688C6
2017-11-01kkmrkkblmbrbkold
56821451316984930115063
37247659D3D688C6


CERT results:
No CERT results for M1603531


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
TF factor-bounds graph:
258
257
this exponent TF target: 61
TF double-checked to: 67
ECM T-Level=25.72 ~= 69-bit
250
260
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280
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Last modified: 2024-02-09T03:30:02+00:00