is 2 1726661 - 1
has 519777 decimal digits
takes 0.094 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
Actual26717.208968.6567%500000150000000.10155.0332%17.310470.2343%
Target2610.177965.5738%70005500000.00291.3448%0.180866.0367%
Difference+6+17.0310+3.0829%+493000+14450000+0.0986+3.6884%+17.1296+4.1976%

Known prime factors (2 factors, 80.9 bits, 0.00468822% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
172666110359967823.3053
3
-136.476e-138.723e-81.601e-7
17266612253830742659505371857.64565265583188
22 × 3 × 13 × 418369123
2015-07-06134183691230.01791.79303.3489

1 Composite Factors:
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-16alpertronManual testing5000001500000012-
skipped known factor: 10359967
--0.101--5.033%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2015-07-06TJAOIManual testing257258*57.645180.0070.3440.025


ECM factoring results:
Total ECM effort:38.428 GHz-days
Estimated T-Level:25.716
DigitsB1CompleteFacMiss
201100014.7850.000%
25500001.68018.633%
302500000.14386.658%
3510000000.01099.013%


ECM Summary

B1B2factorcurvesGHz-days
50000500000025717.64
250000400000004920.79


Lucas-Lehmer results:
No L-L results for M1726661


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-03Oliver KruseGTX-0
10359967
225383074265950537
BC00C4A13818D2__no
2017-11-03ATHec2-1xf
10359967
225383074265950537
BC00C4A13818D2__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
100
101
102
103
104
105
106
100
101
102
103
104
105
106
107
108
109
TF factor-bounds graph:
258
this exponent TF target: 61
TF double-checked to: 67.9
ECM T-Level=25.72 ~= 69-bit
250
260
270
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Last modified: 2023-10-02T12:12:48+00:00