is 2 21055429 - 1
has 6338316 decimal digits
takes 14.922 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L4D4F4818AAEAF706double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual274181.704566.2162 %25500050362500.52972.4564 %182.234267.0461 %
Target2695.670163.7681 %150000225000001.40543.7852 %7.075565.1396 %
Difference+5+176.0344+2.4481 %+105000-17463750-0.8757-1.3289 %+175.1587+1.9065 %

Known prime factors:
No known factors for M21055429

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-11-08Amperiov4_computers2550005036250--0.5304.181%


Trial Factoring results:
575859606162636465666768697071727374
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2001-04-21ANONYMOUSv4_computers212560.000
2002-11-16ANONYMOUSv4_computers212660.355
2015-04-09NRManual testing2662670.710
2017-05-04ramgeisManual testing2672681.420
2017-09-15ramgeisManual testing2682692.839
2017-09-15ramgeisManual testing2692705.679
2021-09-14SRBaseManual testing27027111.36
2021-10-01ANONYMOUSManual testing27127222.71
2021-11-19ANONYMOUSManual testing27227345.43
2021-12-23ANONYMOUSManual testing27327490.86


ECM factoring results:
No ECM results for M21055429


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2003-12-02Amperiov4_computers4D4F4818AAEAF70614.92
2008-10-04ANONYMOUSv4_computers4D4F4818AAEAF70614.92


PRP results:
No PRP results for M21055429


CERT results:
No CERT results for M21055429


P-1 factor-bounds graph:
B1 = 255000, B2 = 5036250 (P-1 stage 2)
B1 = 255000 (P-1 stage 1)
104
105
106
104
105
106
107
TF factor-bounds graph:
274
273
272
271
270
269
268
267
266
256
this exponent TF target: 69
TF double-checked to: 67
250
260
270
280
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Last modified: 2024-02-09T03:30:02+00:00