is 2 1939787 - 1
has 583935 decimal digits
takes 0.105 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L788B45970C947B68double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26830.727569.1176 %80000003200000001.96659.7484 %32.694072.1282 %
Target2620.316766.1290 %80004500000.00251.1518 %0.319266.5192 %
Difference+6+30.4108+2.9886 %+7992000+319550000+1.9639+8.5966%+32.3748+5.6090 %

Known prime factors (1 factor, 90.8 bits, 0.00468046% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
193978721419773330660814317468084492890.791552116632667937621952
26 × 372 × 79 × 2617 × 30480114529
2020-01-08261730480114529129,263,439130.63243.98

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2012-01-28markrtiny275000600000012--0.0466.542%
2015-10-08Bruno Victal5820K.ECM5000001500000012--0.1018.157%
2016-12-15JossManual testing568903568903---3.720%
2016-12-17JossManual testing682683682683---3.963%
2016-12-24JossManual testing819219819219---4.215%
2017-01-04JossManual testing983062983062---4.474%
2017-01-22JossManual testing11796741179674---4.740%
2017-04-12JossManual testing14156081415608012--0.1668.670%
2018-02-04JossManual testing19397872831216012--0.2669.920%
2018-02-04mikrS067800000032000000012--1.96614.767%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-12-21ANONYMOUSv4_computers212580.020
2016-02-23Mark RoseManual testing2582600.158
2010-01-29S485122USB-W2602610.079
2016-02-23Mark RoseManual testing2612620.059
2011-08-27GrunwalderGIMPManual testing212630.823
2016-02-23Mark RoseManual testing2622630.506
2015-05-07lycornManual testing2632641.012
2015-05-07lycornManual testing2642651.926
2015-09-05ramgeisManual testing2652663.852
2017-12-04TJAOIManual testing2662677.705
2019-05-10chuenkitManual testing26726815.41


ECM factoring results:
Total ECM effort:19.889 GHz-days
Estimated T-Level:24.825
DigitsB1CompleteFacMiss
201100010.2370.004%
25500000.96538.101%
302500000.06194.042%
3510000000.00399.712%


ECM Summary

B1B2factorcurvesGHz-days
500005000000664.481
50000500000030.209
50000750000018215.20


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-10ANONYMOUSv4_computers788B45970C947B680.105
2015-06-27MadPooManual testing788B45970C947B680.105


PRP results:
dateuseridcompidcofactorsres64
2020-01-08mrhx
2141977333066081431746808449
CC29EDEC95775518
2020-01-09marssystemsSystem01
2141977333066081431746808449
CC29EDEC95775518


CERT results:
No CERT results for M1939787


P-1 factor-bounds graph:
B1 = 8000000, B2 = 320000000 (P-1 stage 2)
B1 = 8000000 (P-1 stage 1)
B1 = 1939787, B2 = 28312160 (P-1 stage 2)
B1 = 1415608, B2 = 14156080 (P-1 stage 2)
B1 = 1939787 (P-1 stage 1)
B1 = 1415608 (P-1 stage 1)
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 1179674 (P-1 stage 1)
B1 = 983062 (P-1 stage 1)
B1 = 819219 (P-1 stage 1)
B1 = 682683 (P-1 stage 1)
B1 = 275000, B2 = 6000000 (P-1 stage 2)
B1 = 568903 (P-1 stage 1)
B1 = 500000 (P-1 stage 1)
B1 = 275000 (P-1 stage 1)
102
103
104
105
106
107
102
103
104
105
106
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108
109
1010
1011
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
258
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=24.82 ~= 66-bit
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Last modified: 2024-03-13T02:15:48+00:00