is 2 4178191 - 1
has 1257761 decimal digits
takes 0.521 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
Actual2677.111767.1642%2240001468252501.48507.1391%8.596769.5084%
Target2651.746166.1538%220004500000.00821.8730%1.754366.7878%
Difference+2+5.3655+1.0103%+202000+146375250+1.4768+5.2661%+6.8423+2.7206%

Known prime factors (2 factors, 136.3 bits, 0.00326105% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
417819174248223032505591652.721888521169
3 × 29 × 43 × 237509
-432375090.00020.00230.0044
4178191139806520384287318169660792683.5321673050853638420529
7 × 13 × 23 × 71 × 2113 × 2749 × 1938239
2023-01-2027491938239715,3470.01960.0357

1 Composite Factors:
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2023-01-20USAFSS6917th_Scty_Sq2240001468252502683.5321.4851.0422.9707.139%


Trial Factoring results:
No TF results for M4178191


ECM factoring results:
Total ECM effort:0.545 GHz-days
Estimated T-Level:0.577
DigitsB1CompleteFacMiss
20110000.11589.102%
25500000.01198.938%


ECM Summary

B1B2factorcurvesGHz-days
50000500000030.545


Lucas-Lehmer results:
No L-L results for M4178191


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-20kkmrkkblmbrbkManual testing
7424822303250559
F9179F892D2164__no
2018-01-17Oliver KruseGTX-4
7424822303250559
F9179F892D2164__no
2023-01-27TravisJankKRMPNCDT2
7424822303250559
13980652038428731816966079
75CB29DB19A1B5E0no


P-1 factor-bounds graph:
B1 = 224000, B2 = 146825250 (P-1 stage 2)
B1 = 224000 (P-1 stage 1)
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109
TF factor-bounds graph:
this exponent TF target: 65
TF double-checked to: 67.7
ECM T-Level=0.58 ~= -15-bit
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Last modified: 2023-03-25T13:08:14+00:00