is 2 538751 - 1
has 162181 decimal digits
takes 0.008 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
-unknown- L-L tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actualunknown1000000011100000001.478851.2652%1.478851.2652%51.2652%
PrimeNet2400.000050.0000%50001800000.000319.4312%0.000359.7156%9.7156%
GPU722440.000054.5455%90003000000.000514.6544%0.000561.2065%6.6611%
Difference-440.0000-54.5455%+9991000+1109700000+1.4782+36.6109%+1.4782-9.9413%-9.9413%

Known prime factors (3 factors, 236.6 bits, 0.04392538% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
53875175476170494731342.7797004736
26 × 32 × 12161
-64121611.280e-61.529e-52.617e-5
53875140821190742863768631961.8243788502549681
3 × 401 × 3149212427
2015-06-1940131492124271.08373.62826.7764
538751561786583441304512703300077028699114761740132.0455213786920500421462821415431513808
24 × 19 × 193 × 2731 × 10937 × 1184459 × 9929233 × 252968671
2021-08-0799292332529686713.319e+110.49000.5443

4 Composite Factors:
exponentprime factorscomposite factordigitsbits*
5387513081027152306279784175539354319932104.603
53875142401499953467760848478017744534836373011891735055
841
53174.824
53875122932797279439243901898250781602366275827877481221
326385471
59193.869
53875117308797173840366754681128342809746786187904391521
5846417992152875406783
72236.648
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-16T12:41:41alpertronManual testing15000005000000012---0.088--32.909%
2021-08-07T16:49:26ViliamF310000000111000000040132.0451.4790.0162.95842.580%


Trial Factoring results:
Exponent "538751" not found


ECM factoring results:

Old Calculation Method

Total ECM effort:16.148 GHz-days
Estimated T-Level:26.125
DigitsB1CurvesCompleteFacMiss
2011000425 / 1004.2501.396%
2550000425 / 2801.51821.859%
30250000144 / 6400.22579.838%

New Calculation Method

Total ECM effort:16.148 GHz-days
Estimated T-Level:26.125
DigitsB1CompleteFacMiss
201100021.0650.000%
25500002.5547.776%
302500000.23878.844%
3510000000.01898.227%
4030000000.00199.887%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002774.469
50000500000040.065
2500002500000014411.62


Lucas-Lehmer results:
Exponent "538751" not found


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-27T10:27:22Oliver KruseGTX-3
7547617049473
4082119074286376863
853161E06F33EA__no
2017-09-28T09:42:54Oliver KruseManual testing
7547617049473
4082119074286376863
853161E06F33EA__no
2017-11-07T07:21:07kkmrkkblmbrbkc4.xlarge
7547617049473
4082119074286376863
853161E06F33EA__no
2020-04-19T04:19:44Oliver KruseAddPrpType5
7547617049473
4082119074286376863
55050D07A221E0__no
2021-08-07T17:04:22ViliamF3
7547617049473
4082119074286376863
5617865834413045127033000770286991147617
55050D07A221E09Ano


P-1 factor-bounds graph:
B1 = 10000000, B2 = 1110000000 (P-1 stage 2)
B1 = 10000000 (P-1 stage 1)
B1 = 1500000, B2 = 50000000 (P-1 stage 2)
B1 = 1500000 (P-1 stage 1)
100
101
102
103
104
105
106
107
100
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
240
250
260
270
280
290
2100
2110
2120
2130
2140
Last modified: 2021-08-07T17:04:22+00:00