is 2 6968891 - 1
has 2097846 decimal digits
takes 1.520 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L146433A36172E9B2double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272137.229068.0556%3000000750000002.18885.9859%139.417869.9677%
Target2674.263865.6716%450009000000.02902.2389%4.292866.4402%
Difference+5+132.9652+2.3839%+2955000+74100000+2.1599+3.7470%+135.1250+3.5275%

Known prime factors:
No known factors for M6968891

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-09-16ANONYMOUSv4_computers2500087500---0.009--0.431%
2011-09-07Carsten Kossendeymother44000013530000---0.365--3.519%
2021-11-09Seth_TrManual testing30000007500000012---2.189--5.986%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-07-05ANONYMOUSv4_computers21261--0.044--
1998-10-11ANONYMOUSv4_computers21262--0.088--
2005-08-01ANONYMOUSv4_computers21263--0.229--
2014-02-09NesowaManual testing263264--0.282--
2014-02-15lycornManual testing264265--0.536--
2015-06-26VictordeHollanderManual testing265266--1.072--
2016-04-25Gordon SpenceManual testing266267--2.145--
2018-02-27-Anonymous-Manual testing267268--4.289--
2020-04-24TJAOIManual testing268269--8.578--
2021-08-07takahashiManual testing269270--17.16--
2021-09-07SRBaseManual testing270271--34.31--
2021-09-25SRBaseManual testing271272--68.63--


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_computers146433A36172E9B21.520
2001-09-30ANONYMOUSv4_computers146433A36172E9B21.520


PRP results:
No PRP results for M6968891


P-1 factor-bounds graph:
B1 = 3000000, B2 = 75000000 (P-1 stage 2)
B1 = 3000000 (P-1 stage 1)
B1 = 440000, B2 = 13530000 (P-1 stage 2)
B1 = 440000 (P-1 stage 1)
B1 = 25000, B2 = 87500 (P-1 stage 2)
B1 = 25000 (P-1 stage 1)
103
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105
106
107
103
104
105
106
107
108
TF factor-bounds graph:
272
271
270
269
268
267
266
265
264
263
262
261
this exponent TF target: 67
TF double-checked to: 67.8
ECM T-Level=1.15 ~= -13-bit
250
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270
280
Last modified: 2023-03-25T13:08:14+00:00