is 2 1678753 - 1
has 505356 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-L1B6EA8BE232CE1AAdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26717.700068.6567%1000000200000000.13895.6990%17.838970.4430%1.7862%
PrimeNet2570.011463.1579%80001300000.00102.7248%0.012464.1618%1.0039%
GPU722610.183065.5738%7000900000.00081.2552%0.183866.0059%0.4321%
Difference+6+17.5170+3.0829%+993000+19910000+0.1381+4.4437%+17.6551+4.4371%+4.4371%

Known prime factors (1 factor, 76.1 bits, 0.00453602% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1678753837558120770504383926312376.14924945841370663355
3 × 5 × 941 × 1767328471177
2017-09-30941176732847117716,8426,570.812,272

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2011-01-24T01:11:00Jocelyn LaroucheManual testing5000050000---0.003--0.569%
2012-02-29T17:10:00AxonManual testing100000100000---0.007--0.881%
2012-02-29T17:14:00AxonManual testing200000200000---0.014--1.285%
2012-02-29T18:10:00AxonManual testing300000300000---0.020--1.567%
2012-02-29T18:13:00AxonManual testing400000400000---0.027--1.787%
2012-02-29T19:11:00AxonManual testing500000500000---0.034--1.969%
2012-02-29T19:13:00AxonManual testing600000600000---0.041--2.126%
2012-02-29T20:10:00AxonManual testing700000700000---0.048--2.264%
2012-02-29T20:13:00AxonManual testing800000800000---0.055--2.387%
2012-02-29T21:11:00AxonManual testing900000900000---0.061--2.498%
2012-02-29T21:14:00AxonManual testing10000001000000---0.068--2.601%
2012-03-01T06:09:00AxonManual testing10000008000000---0.094--4.732%
2012-03-01T07:10:00AxonManual testing100000020000000---0.139--5.699%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2003-03-27T00:00:00ANONYMOUSv4_computers21258--0.023--
2016-02-23T16:28:45Mark RoseManual testing258260--0.069--
2010-04-27T19:20:00Architects Cubedm1_f2260261--0.091--
2016-02-23T16:28:45Mark RoseManual testing261262--0.183--
2010-09-13T18:09:00GrunwalderGIMPManual testing21263--0.951--
2016-02-23T16:28:45Mark RoseManual testing262263--0.585--
2015-05-13T07:35:00omylistManual testing263264--1.170--
2015-05-14T02:07:00monstManual testing264265--2.226--
2015-10-11T16:52:35ramgeisManual testing265266--4.451--
2017-09-22T15:53:15TJAOIManual testing266267--8.903--


ECM factoring results:

Old Calculation Method

Total ECM effort:14.900 GHz-days
Estimated T-Level:24.482
DigitsB1CurvesCompleteFacMiss
2011000251 / 1002.5108.025%
2550000251 / 2800.89640.737%

New Calculation Method

Total ECM effort:14.900 GHz-days
Estimated T-Level:24.482
DigitsB1CompleteFacMiss
20110008.0970.030%
25500000.73248.105%
302500000.04595.594%
3510000000.00299.794%


ECM Summary

B1B2factorcurvesGHz-days
50000500000024814.72
50000500000030.178


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-17T00:00:00ANONYMOUSv4_computers1B6EA8BE232CE1AA0.079
2016-06-02T10:52:44MadPooManual testing1B6EA8BE232CE1AA0.079


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-01T06:40:23BloodIceMjolnir4
83755812077050438392631
48C43D89907082__no
2017-10-18T14:10:13Oliver KruseThreadripper
83755812077050438392631
48C43D89907082__no


P-1 factor-bounds graph:
B1 = 1000000, B2 = 20000000 (P-1 stage 2)
B1 = 1000000, B2 = 8000000 (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
1011
1012
1013
TF factor-bounds graph:
267
266
265
264
263
262
261
260
258
250
260
270
280
290
2100
Last modified: 2020-01-06T12:25:34+00:00