is 2 2605741 - 1
has 784407 decimal digits
takes 0.181 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L9D871527A8643DE4double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26822.874467.6471 %3000000900000000.77847.7809 %23.652970.1644 %
Target2630.612565.0794 %1200010000000.00661.5310 %0.619165.6140 %
Difference+5+22.2619+2.5677 %+2988000+89000000+0.7718+6.2499%+23.0338+4.5504 %

Known prime factors (1 factor, 80.5 bits, 0.00309048% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
260574117454872199449869334477832580.530334931065663277151
32 × 11775461 × 3160348699
2020-07-3011775461316034869993,97218.43732.344

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-10-31ANONYMOUSv4_computers2048204800--0.0010.669%
2003-11-08Team Prime Ribv4_computers15000217500--0.0031.678%
2010-11-16JossManual testing2000020000--0.0020.628%
2010-12-16markrtiny10000021250006--0.0214.386%
2014-10-10JossManual testing124632124632--0.0131.847%
2016-05-17JossManual testing20000036000006--0.0395.361%
2017-07-10JossManual testing40000040000006--0.0605.868%
2019-12-03masserManual testing20000005000000012--0.46410.322%
2019-12-04BigBrotherWinston30000009000000012--0.77811.484%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-03-26ANONYMOUSv4_computers212590.015
2016-02-23Mark RoseManual testing2592600.029
2009-01-27Sturle Sundegolan.ifi2602610.059
2012-06-24Sebastian HornbostelManual testing2612620.118
2013-01-14dbaughManual testing2622630.377
2015-02-18VictordeHollanderManual testing2632640.753
2015-02-18VictordeHollanderManual testing2642651.434
2016-01-15ramgeisManual testing2652662.868
2017-08-24Gordon SpenceManual testing2662675.736
2019-05-13TJAOIManual testing26726811.47


ECM factoring results:
Total ECM effort:4.096 GHz-days
Estimated T-Level:20.819
DigitsB1CompleteFacMiss
20110001.76917.046%
25500000.16484.900%
302500000.01098.973%


ECM Summary

B1B2factorcurvesGHz-days
500005000000454.003
50000500000010.093


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-26ANONYMOUSv4_computers9D871527A8643DE40.181
2018-06-27kkmrkkblmbrbkold9D871527A8643DE40.181


PRP results:
dateuseridcompidcofactorsres64
2020-07-30M MillerManual testing
1745487219944986933447783
0CB989606A4A59C1
2020-07-31marssystemssystem03
1745487219944986933447783
0CB989606A4A59C1


CERT results:
No CERT results for M2605741


P-1 factor-bounds graph:
B1 = 3000000, B2 = 90000000 (P-1 stage 2)
B1 = 2000000, B2 = 50000000 (P-1 stage 2)
B1 = 3000000 (P-1 stage 1)
B1 = 2000000 (P-1 stage 1)
B1 = 400000, B2 = 4000000 (P-1 stage 2)
B1 = 400000 (P-1 stage 1)
B1 = 200000, B2 = 3600000 (P-1 stage 2)
B1 = 100000, B2 = 2125000 (P-1 stage 2)
B1 = 200000 (P-1 stage 1)
B1 = 124632 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 15000, B2 = 217500 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
103
104
105
106
107
108
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
259
this exponent TF target: 63
TF double-checked to: 67
ECM T-Level=20.82 ~= 53-bit
250
260
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290
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Last modified: 2024-02-29T14:28:04+00:00