is 2 2825671 - 1
has 850612 decimal digits
takes 0.218 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L6B8308B536108796double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26821.094167.6471 %50000002000000001.74989.1662 %22.843870.6126 %
Target2630.564865.0794 %1600013000000.00961.8260 %0.574565.7170 %
Difference+5+20.5292+2.5677 %+4984000+198700000+1.7402+7.3402%+22.2694+4.8956 %

Known prime factors (1 factor, 71.6 bits, 0.00253566% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
282567137037578349618308466332271.649655376693705996
22 × 47 × 107 × 32579871431
2021-03-1610732579871431169.19198.79371.29

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-11-28ANONYMOUSv4_computers2048204800--0.0010.683%
2016-09-16JossManual testing13200033000006--0.0385.054%
2016-09-21JossManual testing1320003630000--0.0405.151%
2016-12-19JossManual testing190080190080---2.272%
2017-01-10JossManual testing228096228096---2.458%
2017-03-15JossManual testing32845832845806--0.0605.586%
2018-08-30JossManual testing602578602578---3.585%
2018-09-03JossManual testing656916656916---3.695%
2018-09-05JossManual testing6569161313832---4.628%
2018-09-12JossManual testing6569162627664--0.0945.567%
2019-11-10masserManual testing30000003000000012--0.5529.773%
2020-01-24masserManual testing500000020000000012--1.92813.171%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2016-02-23Mark RoseManual testing212600.054
2009-02-12Sturle Sundegigi.ifi2602610.054
2012-02-17markroldgamer2612620.109
2013-01-10dbaughManual testing2622630.347
2015-04-21VictordeHollanderManual testing2632640.695
2015-04-21VictordeHollanderManual testing2642651.322
2016-02-13ramgeisManual testing2652662.645
2017-10-28Gordon SpenceManual testing2662675.289
2019-01-03chuenkitManual testing26726810.58


ECM factoring results:
Total ECM effort:7.693 GHz-days
Estimated T-Level:21.352
DigitsB1CompleteFacMiss
20110002.9235.377%
25500000.27076.303%
302500000.01798.309%


ECM Summary

B1B2factorcurvesGHz-days
500005000000727.286
50000500000040.407


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-05-16ANONYMOUSv4_computers6B8308B5361087960.218
1999-09-14ANONYMOUSv4_computers6B8308B5361087960.218
2018-09-08kkmrkkblmbrbkold6B8308B5361087960.213


PRP results:
dateuseridcompidcofactorsres64
2021-03-17marssystemssystem11
3703757834961830846633
0562A68A54BF0DC8


CERT results:
dateuseridcompid
2021-03-17Oliver KruseThreadripper-PC


P-1 factor-bounds graph:
B1 = 5000000, B2 = 200000000 (P-1 stage 2)
B1 = 5000000 (P-1 stage 1)
B1 = 3000000, B2 = 30000000 (P-1 stage 2)
B1 = 3000000 (P-1 stage 1)
B1 = 656916, B2 = 2627664 (P-1 stage 2)
B1 = 656916, B2 = 1313832 (P-1 stage 2)
B1 = 656916 (P-1 stage 1)
B1 = 602578 (P-1 stage 1)
B1 = 328458, B2 = 3284580 (P-1 stage 2)
B1 = 328458 (P-1 stage 1)
B1 = 132000, B2 = 3630000 (P-1 stage 2)
B1 = 132000, B2 = 3300000 (P-1 stage 2)
B1 = 228096 (P-1 stage 1)
B1 = 190080 (P-1 stage 1)
B1 = 132000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
101
102
103
104
105
106
107
101
102
103
104
105
106
107
108
109
1010
1011
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
this exponent TF target: 63
TF double-checked to: 67
ECM T-Level=21.35 ~= 54-bit
250
260
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Last modified: 2024-02-29T14:28:04+00:00