is 2 6940561 - 1
has 2089318 decimal digits
takes 1.513 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L9CA9DFF8D968B55Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272137.789168.0556%40000004568186709.06528.0804%146.854370.6368%
Target2674.281265.6716%4500072000000.13752.2374%4.418766.4397%
Difference+5+133.5079+2.3839%+3955000+449618670+8.9277+5.8430%+142.4356+4.1971%

Known prime factors (1 factor, 82.3 bits, 0.00118608% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
694056160385981888231932054465292582.320435022341048741824
26 × 7 × 293 × 12743 × 260072387		2021-12-0212743260072387147,9644.48398.3676

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-10-20ANONYMOUSv4_computers3000030000---0.009--0.234%
2011-09-05Carsten Kossendeymother44000013310000---0.361--3.506%
2021-11-17Seth_TrManual testing30000007500000012---2.189--5.983%
2021-12-02Seth_TrManual testing40000004568186702582.3209.0653.02718.138.080%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-01-02ANONYMOUSv4_computers21261--0.044--
1999-01-02ANONYMOUSv4_computers21262--0.089--
2004-10-18ANONYMOUSv4_computers21263--0.230--
2014-02-09NesowaManual testing263264--0.283--
2014-02-16lycornManual testing264265--0.538--
2015-06-26VictordeHollanderManual testing265266--1.077--
2016-04-05Gordon SpenceManual testing266267--2.153--
2018-02-27-Anonymous-Manual testing267268--4.307--
2020-04-24TJAOIManual testing268269--8.613--
2021-07-28takahashiManual testing269270--17.23--
2021-08-11SRBaseManual testing270271--34.45--
2021-09-25SRBaseManual testing271272--68.91--


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)
1999-03-26Ken Warnerv4_computersB168A46CADAC6A__1.513
1999-06-15ANONYMOUSv4_computers9CA9DFF8D968B55E1.513
2000-03-22Ken Warnerv4_computersB168A46CADAC6A__1.513
2002-01-02ANONYMOUSv4_computers9CA9DFF8D968B55E1.513
2002-03-03ANONYMOUSv4_computers9CA9DFF8D968B55E1.513


PRP results:
dateuseridcompidcofactorsres64PRP
2021-12-08LaurVZero818
6038598188823193205446529
FE7E3EB221C1A1D0no


P-1 factor-bounds graph:
B1 = 4000000, B2 = 456818670 (P-1 stage 2)
B1 = 3000000, B2 = 75000000 (P-1 stage 2)
B1 = 4000000 (P-1 stage 1)
B1 = 3000000 (P-1 stage 1)
B1 = 440000, B2 = 13310000 (P-1 stage 2)
B1 = 440000 (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
261
this exponent TF target: 67
TF double-checked to: 67.8
ECM T-Level=1.15 ~= -13-bit
250
260
270
280
290
Last modified: 2023-06-05T21:50:05+00:00