is 2 1640971 - 1
has 493982 decimal digits
takes 0.073 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
-unknown- primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26718.107568.6567%500000150000000.08355.0024%18.191170.2246%1.5679%
PrimeNet2570.011763.1579%70001200000.00092.5607%0.012664.1013%0.9434%
GPU722610.187265.5738%6500700000.00061.1200%0.187865.9593%0.3856%
Difference+6+17.9203+3.0829%+493500+14930000+0.0829+3.8824%+18.0032+4.2653%+1.1823%

Known prime factors (2 factors, 99.0 bits, 0.00603446% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
164097142435510071031.9831293
3 × 431
-34312.231e-101.705e-62.868e-6
16409711518430417892080229692167.04146266217315604
22 × 11 × 13 × 31 × 97 × 733 × 36697
2015-05-137333669723.4850.00020.0002

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
16409716443536928905367876025790797833099.024
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2015-05-13T11:36:00alpertronManual testing50000015000000122167.0410.0320.1470.0655.002%


Trial Factoring results:
No TF results for M1640971


ECM factoring results:
Total ECM effort:14.108 GHz-days
Estimated T-Level:24.466
DigitsB1CompleteFacMiss
20110009.6540.006%
25500000.89340.933%
302500000.05694.522%
3510000000.00399.737%


ECM Summary

B1B2factorcurvesGHz-days
50000500000025114.11


Lucas-Lehmer results:
No L-L results for M1640971


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-02T16:57:02Oliver KruseGTX-1
4243551007
151843041789208022969
75A40FA1DFE3E9__no
2017-11-02T02:24:36kkmrkkblmbrbkc4.xlarge
4243551007
151843041789208022969
75A40FA1DFE3E9__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
TF factor-bounds graph:
267
230
240
250
260
270
280
290
2100
Last modified: 2019-11-18T17:52:34+00:00