is 2 1687729 - 1
has 508058 decimal digits
takes 0.079 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L4D571E5185A3B75Ddouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26717.605968.6567%1000000200000000.13895.7024%17.744770.4440%1.7873%
PrimeNet2570.011463.1579%80001300000.00102.7275%0.012464.1628%1.0049%
GPU722610.182065.5738%7000900000.00081.2567%0.182866.0064%0.4326%
Difference+6+17.4239+3.0829%+993000+19910000+0.1381+4.4458%+17.5619+4.4376%+4.4376%

Known prime factors (1 factor, 75.9 bits, 0.00449948% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1687729724321073667773575123212375.93921458453154143040
26 × 33 × 5 × 7 × 109 × 3255068497
2014-08-2610932550684974,946.012.10222.603

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2011-01-25T02:46:00Jocelyn LaroucheManual testing5000050000---0.003--0.570%
2012-02-29T17:11:00AxonManual testing100000100000---0.007--0.882%
2012-02-29T17:15:00AxonManual testing200000200000---0.014--1.286%
2012-02-29T18:10:00AxonManual testing300000300000---0.020--1.568%
2012-02-29T18:13:00AxonManual testing400000400000---0.027--1.788%
2012-02-29T19:11:00AxonManual testing500000500000---0.034--1.971%
2012-02-29T19:14:00AxonManual testing600000600000---0.041--2.128%
2012-02-29T20:10:00AxonManual testing700000700000---0.048--2.265%
2012-02-29T20:13:00AxonManual testing800000800000---0.055--2.389%
2012-02-29T21:12:00AxonManual testing900000900000---0.061--2.500%
2012-02-29T21:14:00AxonManual testing10000001000000---0.068--2.603%
2012-03-01T06:09:00AxonManual testing10000008000000---0.094--4.735%
2012-03-01T07:10:00AxonManual testing100000020000000---0.139--5.702%
2016-03-17T19:18:44alpertronManual testing5000001500000012---0.088--5.019%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-11-21T00:00:00dakrugerv4_computers21257--0.011--
2003-03-16T00:00:00ANONYMOUSv4_computers21258--0.023--
2022-03-08T23:06:22LordJuliusManual testing258260--0.068--
2010-04-26T14:20:00Architects Cubedm1_76l260261--0.091--
2010-09-26T01:51:00GrunwalderGIMPManual testing21263--0.946--


ECM factoring results:

Old Calculation Method

Total ECM effort:14.908 GHz-days
Estimated T-Level:24.482
DigitsB1CurvesCompleteFacMiss
2011000251 / 1002.5108.025%
2550000251 / 2800.89640.737%

New Calculation Method

Total ECM effort:14.908 GHz-days
Estimated T-Level:24.482
DigitsB1CompleteFacMiss
20110008.0970.030%
25500000.73248.105%
302500000.04595.594%
3510000000.00299.794%


ECM Summary

B1B2factorcurvesGHz-days
50000500000025014.85
50000500000010.059


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-11-21T00:00:00dakrugerv4_computers4D571E5185A3B75D0.079


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-03T01:16:42Oliver KruseGTX-2
72432107366777357512321
E70EB8DD90E456__no
2017-11-03T11:50:55Chang Chia-Tcheexbpc13
72432107366777357512321
E70EB8DD90E456__no


P-1 factor-bounds graph:
B1 = 1000000, B2 = 20000000 (P-1 stage 2)
B1 = 1000000, B2 = 8000000 (P-1 stage 2)
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 900000 (P-1 stage 1)
B1 = 800000 (P-1 stage 1)
B1 = 700000 (P-1 stage 1)
B1 = 600000 (P-1 stage 1)
B1 = 500000 (P-1 stage 1)
B1 = 400000 (P-1 stage 1)
B1 = 300000 (P-1 stage 1)
B1 = 200000 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
267
263
261
260
258
257
250
260
270
280
290
2100
Last modified: 2022-03-08T23:06:22+00:00