is 2 1918537 - 1
has 577538 decimal digits
takes 0.104 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L932BF001146560EBdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26715.487868.6567 %500000150000000.10155.0975 %15.589370.2544 %
Target2610.160165.5738 %100008500000.00441.7613 %0.164566.1801 %
Difference+6+15.3277+3.0829 %+490000+14150000+0.0971+3.3362%+15.4248+4.0743 %

Known prime factors (1 factor, 70.2 bits, 0.00366139% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
191853713991669120796703263612270.245364644234664140
22 × 3 × 5 × 247717 × 24533657
2009-08-0224771724533657171.490.12360.1964

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2016-03-17alpertronManual testing5000001500000012---8.910%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2002-12-25ANONYMOUSv4_computers212580.020
2022-03-09LordJuliusManual testing21260
2009-06-02Architects Cubedi4l_12602610.080


ECM factoring results:
Total ECM effort:39.215 GHz-days
Estimated T-Level:25.701
DigitsB1CompleteFacMiss
201100015.0480.000%
25500001.67418.753%
302500000.14086.922%
3510000000.01099.052%


ECM Summary

B1B2factorcurvesGHz-days
10.103
500005000000241.613
50000660000021717.00
500006750000141.109
250000400000004519.39


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-15ANONYMOUSv4_computers932BF001146560EB0.104


PRP results:
dateuseridcompidcofactorsres64
2017-10-04Oliver KruseGTX-2
1399166912079670326361
A7A76A471300B6A3
2017-11-09kkmrkkblmbrbkc4.large
1399166912079670326361
A7A76A471300B6A3


CERT results:
No CERT results for M1918537


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
104
105
106
104
105
106
107
108
TF factor-bounds graph:
261
260
258
this exponent TF target: 61
TF double-checked to: 67
ECM T-Level=25.7 ~= 69-bit
250
260
270
280
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Last modified: 2024-03-13T02:15:48+00:00