is 2 8121011 - 1
has 2444668 decimal digits
takes 2.120 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L82161D610825D2F4double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272117.760468.0556 %65000005757565440121.092711.4978 %238.853171.7285 %
Target2673.658965.6716 %5500060000000.14352.5730 %3.802366.5549 %
Difference+5+114.1015+2.3839 %+6445000+5751565440+120.9492+8.9248%+235.0507+5.1736 %

Known prime factors (1 factor, 90.9 bits, 0.00111990% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
812101123875394866434394738498872972890.948146997675944746255968
25 × 3 × 107 × 88663 × 113947 × 1416479
2021-11-25113947141647931,597,6760.07000.0878

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2002-11-16ANONYMOUSv4_computers450007312502--0.0312.178%
2012-10-17NesowaEPC10000019750006--0.0773.235%
2021-11-25FlaukrotistColab_AK25000000500000012890.9481.8935.306%
2022-10-17FlaukrotistColab_AK265000005757565440
skipped known factor: 2387539486643439473849887297
--128.215.917%


Trial Factoring results:
57585960616263646566676869707172
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-08-30Tom 7v4_computers212620.038
1998-09-06ANONYMOUSv4_computers212630.121
2013-09-15AxelssonManual testing2632640.242
2013-12-26David CampeauManual testing2642650.460
2015-05-25snme2pm1Manual testing2652660.920
2015-11-30snme2pm1Manual testing2662671.840
2018-07-03chuenkitManual testing2672683.681
2019-12-02mnd9Manual testing2682697.361
2021-08-20SRBaseManual testing26927014.72
2021-08-27SRBaseManual testing27027129.45
2021-09-30SRBaseManual testing27127258.89


ECM factoring results:
Total ECM effort:2.382 GHz-days
Estimated T-Level:1.154
DigitsB1CompleteFacMiss
20110000.23179.392%
25500000.02197.887%
302500000.00199.865%


ECM Summary

B1B2factorcurvesGHz-days
50000500000062.382


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-09-30ANONYMOUSv4_computers82161D610825D2F42.120
2002-12-02ANONYMOUSv4_computers82161D610825D2F42.120


PRP results:
dateuseridcompidcofactorsres64
2021-12-05RichD0Linux-5b
2387539486643439473849887297
A0AE617B5393049C


CERT results:
dateuseridcompid
2021-12-05ZeroOf149Tairitsu


P-1 factor-bounds graph:
B1 = 6500000, B2 = 5757565440 (P-1 stage 2)
B1 = 6500000 (P-1 stage 1)
B1 = 5000000 (P-1 stage 1)
B1 = 100000, B2 = 1975000 (P-1 stage 2)
B1 = 100000 (P-1 stage 1)
B1 = 45000, B2 = 731250 (P-1 stage 2)
B1 = 45000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
109
1010
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
ECM T-Level=1.15 ~= -13-bit
250
260
270
280
290
2100
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Last modified: 2024-03-13T02:15:48+00:00