is 2 1508389 - 1
has 454071 decimal digits
takes 0.067 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LDC758F1893F97B4Ddouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26979.148569.5652%100000002000000001.31818.3596%80.466772.1094%2.5442%
PrimeNet2570.012763.1579%65001000000.00082.3430%0.013564.0211%0.8632%
GPU722610.203665.5738%6000500000.00050.9491%0.204265.9005%0.3268%
Difference+8+78.9449+3.9914%+9994000+199950000+1.3176+7.4104%+80.2625+6.2089%+6.2089%

Known prime factors:
No known factors for M1508389

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2011-01-26T13:19:00James HeinrichWHS800001280000---0.009--1.683%
2013-11-16T02:27:00David Campeaui5-2500k93500027115000---0.153--4.917%
2015-01-22T10:36:00VictordeHollanderManual testing10000000200000000---1.318--8.360%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2003-08-08T00:00:00ANONYMOUSv4_computers21258--0.025--
2016-02-23T16:28:36Mark RoseManual testing258261--0.178--
2016-02-23T16:28:36Mark RoseManual testing261262--0.204--
2010-04-04T04:46:00GrunwalderGIMPManual testing21263--1.058--
2016-02-23T16:28:36Mark RoseManual testing262263--0.651--
2015-01-13T21:57:00snme2pm1Manual testing263264--1.302--
2015-01-13T21:57:00snme2pm1Manual testing264265--2.477--
2015-09-27T20:41:25ramgeisManual testing265266--4.954--
2018-03-19T15:07:59TJAOIManual testing266267--9.91--
2018-06-06T17:06:40ramgeisManual testing267268--19.82--
2019-11-04T13:15:47mnd9Manual testing268269--39.63--


ECM factoring results:

Old Calculation Method

Total ECM effort:31.345 GHz-days
Estimated T-Level:22.089
DigitsB1CurvesCompleteFacMiss
2011000117 / 1001.17030.854%
2550000117 / 2800.41865.796%
3025000085 / 6400.13387.554%

New Calculation Method

Total ECM effort:31.345 GHz-days
Estimated T-Level:22.089
DigitsB1CompleteFacMiss
20110009.6400.007%
25500001.44223.645%
302500000.15585.631%
3510000000.01398.710%


ECM Summary

B1B2factorcurvesGHz-days
500005000000321.784
25000025000000102.787
250000350000003410.94
250000500000004115.83


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-02-21T00:00:00ANONYMOUSv4_computersDC758F1893F97B4D0.067
2015-07-21T00:18:00MadPooManual testingDC758F1893F97B4D0.067


PRP results:
No PRP results for M1508389


P-1 factor-bounds graph:
B1 = 10000000, B2 = 200000000 (P-1 stage 2)
B1 = 10000000 (P-1 stage 1)
B1 = 935000, B2 = 27115000 (P-1 stage 2)
B1 = 935000 (P-1 stage 1)
B1 = 80000, B2 = 1280000 (P-1 stage 2)
B1 = 80000 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-03-17T11:20:44+00:00