is 2 1521769 - 1
has 458099 decimal digits
takes 0.068 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L2DED58822956EDA7double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26719.525968.6567%500000150000000.08354.9570%19.609570.2104%1.5537%
PrimeNet2570.012663.1579%65001100000.00082.4117%0.013464.0464%0.8885%
GPU722610.201965.5738%6500550000.00061.0130%0.202465.9225%0.3487%
Difference+6+19.3240+3.0829%+493500+14945000+0.0830+3.9440%+19.4070+4.2879%+4.2879%

Known prime factors (1 factor, 65.9 bits, 0.00433362% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1521769711580289335987889272065.94823380036304327
53 × 15629 × 28225271
2013-08-0815629282252718.16040.10060.1860

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2011-01-29T11:48:00James HeinrichWHS800001340000---0.010--2.191%
2016-03-17T19:15:50alpertronManual testing5000001500000012---0.084--4.957%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1997-11-12T00:00:00ANONYMOUSv4_computers21256--0.006--
1998-12-27T00:00:00ANONYMOUSv4_computers21257--0.013--
2003-08-08T00:00:00ANONYMOUSv4_computers21258--0.025--
2010-04-25T12:20:00Architects Cubeda3_bu2260261--0.101--
2010-05-04T02:59:00GrunwalderGIMPManual testing21263--1.049--


ECM factoring results:

Old Calculation Method

Total ECM effort:13.948 GHz-days
Estimated T-Level:24.464
DigitsB1CurvesCompleteFacMiss
2011000250 / 1002.5008.106%
2550000250 / 2800.89340.883%

New Calculation Method

Total ECM effort:13.948 GHz-days
Estimated T-Level:24.464
DigitsB1CompleteFacMiss
20110008.0650.031%
25500000.72948.246%
302500000.04595.611%
3510000000.00299.795%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
50000500000025013.95


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1997-11-12T00:00:00ANONYMOUSv4_computers2DED58822956EDA70.068
1999-02-14T00:00:00ANONYMOUSv4_computers2DED58822956EDA70.068


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-01T13:31:24Oliver KruseGTX-1
71158028933598788927
791B2F4D1C282B__no
2017-10-29T21:25:46kkmrkkblmbrbkc4.xlarge
71158028933598788927
791B2F4D1C282B__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
B1 = 80000, B2 = 1340000 (P-1 stage 2)
B1 = 80000 (P-1 stage 1)
103
104
105
106
103
104
105
106
107
108
TF factor-bounds graph:
267
263
261
258
257
256
250
260
270
280
290
2100
Last modified: 2019-06-07T09:13:57+00:00