is 2 61528391 - 1
has 18521892 decimal digits
takes 144.535 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual27331.088864.3836 %----31.088864.3836 %
Target27462.180564.8649 %4000006500000013.35073.7182 %75.531266.1712 %
Difference-1-31.0917-0.4813 %-400000-65000000-13.3507-3.7182 %-44.4424-1.7877 %

Known prime factors (1 factor, 103.3 bits, 0.00016787% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
615283911237316640412192566805940513366332103.287100548431407233822090841
7 × 172 × 3251 × 53719 × 389299 × 731057
2013-03-163892997310572.154e+91.38942.6987

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2013-03-16Just factoring!32103.2874.1100.000%


Trial Factoring results:
575859606162636465666768697071727374
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2003-06-09Gordon Spencev4_computers212590.001
2003-11-08Gordon Spencev4_computers212600.001
2004-04-09ANONYMOUSv4_computers212620.005
2022-03-29LordJuliusManual testing262263
2009-02-02ANONYMOUS2632660.214
2009-02-04S36049Wolle42662670.243
2009-02-05S36049Wolle42672680.486
2009-07-29plusplusCF7C6E8702682690.972
2011-11-14JaeckelH0F4092692701.943
2012-09-06Clown_RoyalManual testing2702713.886
2013-03-15Kyle AskineManual testing27127323.32


ECM factoring results:
No ECM results for M61528391


Lucas-Lehmer results:
No L-L results for M61528391


PRP results:
No PRP results for M61528391


CERT results:
No CERT results for M61528391


P-1 factor-bounds graph:
104
105
106
104
105
106
TF factor-bounds graph:
273
271
270
269
268
267
266
263
262
260
259
this exponent TF target: 74
TF double-checked to: 67
250
260
270
280
290
2100
2110
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Last modified: 2024-03-13T02:15:48+00:00