is 2 248903 - 1
has 74928 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-L97969584CC953DCFdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual267119.379573.1343%30000000101202470268904,486.311423.4115%4,605.690979.4240%6.2897%
PrimeNet2400.000055.0000%2600700000.000114.1968%0.000161.3885%6.3885%
GPU722440.000059.0909%45001100000.000110.1533%0.000163.2445%4.1536%
Difference+23+119.3795+14.0434%+29995500+10120246916890+4,486.3113+13.2582%+4,605.6908+16.1794%+16.1794%

Known prime factors (1 factor, 96.8 bits, 0.03889576% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2489031391647471326739795229810043593096.813279556186813083770631493
372 × 67 × 3111677 × 979481747483
2015-11-2631116779794817474838.475e+10434.21810.93

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2000-11-25T00:00:00ANONYMOUSv4_computers1000004000000---0.003--2.243%
2001-06-09T00:00:00ANONYMOUSv4_computers10000010000000---0.005--2.710%
2002-06-02T00:00:00ANONYMOUSv4_computers327683276800---0.002--1.551%
2002-08-10T00:00:00ANONYMOUSv4_computers655366553600---0.003--2.232%
2003-03-07T00:00:00ANONYMOUSv4_computers13107213107200---0.007--3.040%
2003-11-08T00:00:00ANONYMOUSv4_computers26214426214400---0.014--3.965%
2011-02-07T22:22:00Jocelyn LaroucheManual testing20000002000000---0.016--2.599%
2011-07-24T13:13:00Jocelyn LaroucheManual testing20162172016217---0.016--2.607%
2012-02-26T15:17:00Jocelyn LaroucheManual testing25202712520271---0.021--2.823%
2013-10-13T11:04:00David Campeaui5-2500k257000074530000---0.053--6.368%
2014-12-24T22:05:00thelegendarymudkipi5-4670k10000000250000000---0.188--8.540%
2021-08-09T02:28:39Oliver KruseOllaptop30000000300000000024---1.561--12.564%
2022-04-17T17:59:55Oliver KruseThreadripper-PC3000000010120247026890-
skipped known factor: 139164747132673979522981004359
--4,486--23.412%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-24T00:00:00ANONYMOUSv4_computers252253--0.002--
2000-04-27T00:00:00ANONYMOUSv4_computers21254--0.010--
2022-03-07T05:45:17LordJuliusManual testing254255--0.010--
2001-02-18T00:00:00ANONYMOUSv4_computers21256--0.039--
2002-04-14T00:00:00ANONYMOUSv4_computers21257--0.077--
2022-03-07T05:45:17LordJuliusManual testing257258--0.077--
2008-12-31T12:10:00Sturle Sundegluck.ifi258259--0.154--
2009-01-24T07:08:00Sturle Sundekraus.ifi259260--0.309--
2013-07-13T18:11:00lycornasteroid260261--0.617--
2015-08-10T06:35:00snme2pm1Manual testing261262--1.234--


ECM factoring results:

Old Calculation Method

Total ECM effort:9.730 GHz-days
Estimated T-Level:27.055
DigitsB1CurvesCompleteFacMiss
2011000557 / 1005.5700.371%
2550000557 / 2801.98913.631%
30250000263 / 6400.41166.282%

New Calculation Method

Total ECM effort:9.730 GHz-days
Estimated T-Level:27.055
DigitsB1CompleteFacMiss
201100031.4010.000%
25500004.0491.744%
302500000.39767.201%
3510000000.03196.937%
4030000000.00299.799%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002941.757
250000250000002407.173
2500002500000020.060
25000038500000210.740


Lucas-Lehmer results:
No L-L results for M248903


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-22T06:56:46Oliver KruseOllaptop
139164747132673979522981004359
92EB5AAAD27C6F__no
2017-09-22T10:06:06Oliver KruseManual testing
139164747132673979522981004359
92EB5AAAD27C6F__no
2017-10-12T16:31:01Oliver KruseGTX-292EB5AAAD27C6F__no
2017-11-06T16:36:27kkmrkkblmbrbkc4.xlarge
139164747132673979522981004359
92EB5AAAD27C6F__no
2020-04-17T20:15:16Oliver KruseAddPrpType5
139164747132673979522981004359
C0D56F68653C3B__no


P-1 factor-bounds graph:
B1 = 30000000, B2 = 10120247026890 (P-1 stage 2)
B1 = 30000000, B2 = 3000000000 (P-1 stage 2)
B1 = 30000000 (P-1 stage 1)
B1 = 10000000, B2 = 250000000 (P-1 stage 2)
B1 = 10000000 (P-1 stage 1)
B1 = 2570000, B2 = 74530000 (P-1 stage 2)
B1 = 2570000 (P-1 stage 1)
B1 = 2520271 (P-1 stage 1)
B1 = 2016217 (P-1 stage 1)
B1 = 2000000 (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 = 100000, B2 = 4000000 (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
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109
1010
1011
1012
1013
1014
TF factor-bounds graph:
267
262
261
260
259
258
257
256
255
254
253
250
260
270
280
290
2100
Last modified: 2022-04-17T17:59:55+00:00