is 2 6947903 - 1
has 2091528 decimal digits
takes 1.515 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L11CD231A532F844Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272137.643568.0556%40000004568186709.06528.0812%146.708670.6371%
Target2674.276765.6716%4500072000000.13752.2378%4.414266.4398%
Difference+5+133.3668+2.3839%+3955000+449618670+8.9277+5.8435%+142.2945+4.1972%

Known prime factors:
No known factors for M6947903

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-09-10ANONYMOUSv4_computers3000030000---0.009--0.234%
2011-09-05Carsten Kossendeymother44500013350000---0.363--3.514%
2021-11-05Seth_TrManual testing20000005800000012---1.597--5.520%
2021-12-03Seth_TrManual testing4000000456818670---9.065--8.081%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-07-11ANONYMOUSv4_computers21262--0.088--
1998-08-02ANONYMOUSv4_computers21262--0.088--
1998-09-13ANONYMOUSv4_computers21262--0.088--
1999-04-13ANONYMOUSv4_computers21262--0.088--
2005-03-20ANONYMOUSv4_computers21263--0.230--
2014-02-09NesowaManual testing263264--0.283--
2014-02-16lycornManual testing264265--0.538--
2015-06-26VictordeHollanderManual testing265266--1.076--
2016-04-05Gordon SpenceManual testing266267--2.151--
2018-02-26-Anonymous-Manual testing267268--4.302--
2020-04-10TJAOIManual testing268269--8.604--
2021-07-28takahashiManual testing269270--17.21--
2021-08-12SRBaseManual testing270271--34.42--
2021-09-28SRBaseManual testing271272--68.83--


ECM factoring results:
Total ECM effort:1.989 GHz-days
Estimated T-Level:1.154
DigitsB1CompleteFacMiss
20110000.23179.392%
25500000.02197.887%
302500000.00199.865%


ECM Summary

B1B2factorcurvesGHz-days
50000500000061.989


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-26ANONYMOUSv4_computersA057E58058338A__1.515
1999-05-30ANONYMOUSv4_computers11CD231A532F844E1.515
2001-11-10ANONYMOUSv4_computers11CD231A532F844E1.515


PRP results:
No PRP results for M6947903


P-1 factor-bounds graph:
B1 = 4000000, B2 = 456818670 (P-1 stage 2)
B1 = 2000000, B2 = 58000000 (P-1 stage 2)
B1 = 4000000 (P-1 stage 1)
B1 = 2000000 (P-1 stage 1)
B1 = 445000, B2 = 13350000 (P-1 stage 2)
B1 = 445000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
109
TF factor-bounds graph:
272
271
270
269
268
267
266
265
264
263
262
this exponent TF target: 67
TF double-checked to: 67.8
ECM T-Level=1.15 ~= -13-bit
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280
Last modified: 2023-06-05T21:50:05+00:00