is 2 157991 - 1
has 47561 decimal digits
takes 0.001 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L62F7F308559A0B55double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual267188.073573.1343%10000000020000000000.975512.1221%189.049076.3910%3.2567%
PrimeNet2400.000055.0000%1700360000.000010.9844%0.000059.9430%4.9430%
GPU722440.000059.0909%2800550000.00007.4796%0.000062.1508%3.0598%
Difference+23+188.0735+14.0434%+99997200+1999945000+0.9754+4.6425%+189.0489+14.2403%+14.2403%

Known prime factors (1 factor, 86.0 bits, 0.05441033% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
157991754340103973241402419556332685.963238728821253502225576
23 × 72 × 8663 × 396217 × 177426043
2009-01-1239621717742604396,787,5170.04810.0865

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-04-29T00:00:00ANONYMOUSv4_computers10000010000000---0.003--2.529%
2002-06-02T00:00:00ANONYMOUSv4_computers327683276800---0.001--1.429%
2002-07-20T00:00:00ANONYMOUSv4_computers655366553600---0.002--2.073%
2003-02-09T00:00:00ANONYMOUSv4_computers13107213107200---0.004--2.845%
2003-10-08T00:00:00ANONYMOUSv4_computers26214426214400---0.008--3.734%
2016-12-25T01:34:25kkmrkkblmbrbkManual testing100000000200000000012-
skipped known factor: 75434010397324140241955633
--0.975--12.122%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-04T00:00:00ANONYMOUSv4_computers252253--0.004--
2000-05-05T00:00:00ANONYMOUSv4_computers21254--0.015--
2022-03-07T03:54:06LordJuliusManual testing254255--0.015--
2001-01-08T00:00:00ANONYMOUSv4_computers21256--0.061--
2002-07-14T00:00:00ANONYMOUSv4_computers21257--0.122--
2022-03-07T03:54:06LordJuliusManual testing257258--0.122--
2009-01-02T16:55:00Sturle Sundegooch.ifi258259--0.243--


ECM factoring results:

Old Calculation Method

Total ECM effort:12.008 GHz-days
Estimated T-Level:29.750
DigitsB1CurvesCompleteFacMiss
2011000884 / 1008.8400.014%
2550000884 / 2803.1574.231%
30250000608 / 6400.95038.645%
3510000009 / 15660.00699.427%

New Calculation Method

Total ECM effort:12.008 GHz-days
Estimated T-Level:29.750
DigitsB1CompleteFacMiss
201100066.5700.000%
25500009.7190.006%
302500001.04035.348%
3510000000.08891.614%
4030000000.00699.395%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
5000050000002760.960
2500002500000059910.42
100000010000000090.626


Lucas-Lehmer results:
No L-L results for M157991


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-21T23:32:24Oliver KruseOllaptop
75434010397324140241955633
62D74AF5B1D6A4__no
2017-09-22T10:03:15Oliver KruseManual testing
75434010397324140241955633
62D74AF5B1D6A4__no
2017-10-11T23:17:53kkmrkkblmbrbkc4.xlarge62D74AF5B1D6A4__no
2020-04-17T15:48:50Oliver KruseAddPrpType5
75434010397324140241955633
E282BBF760A201__no


P-1 factor-bounds graph:
B1 = 100000000, B2 = 2000000000 (P-1 stage 2)
B1 = 100000000 (P-1 stage 1)
B1 = 262144, B2 = 26214400 (P-1 stage 2)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 100000, B2 = 10000000 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 262144 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 65536 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
103
104
105
106
107
108
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
267
259
258
257
256
255
254
253
250
260
270
280
290
2100
Last modified: 2022-03-07T03:54:06+00:00