is 2 1912487 - 1
has 575716 decimal digits
takes 0.104 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
Actual26715.536868.6567 %500000150000000.10155.0956 %15.638370.2538 %
Target2610.160665.5738 %100008500000.00441.7602 %0.165066.1797 %
Difference+6+15.3762+3.0829 %+490000+14150000+0.0971+3.3354%+15.4733+4.0741 %

Known prime factors (2 factors, 114.4 bits, 0.00598032% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1912487207408335405991444.2385422477
2287 × 2371
-228723711.225e-60.00020.0004
191248712966198828102640005432270.135338987894508633
3 × 23 × 29 × 439 × 385898047
2018-05-01439385898047124.941.65393.0890

1 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2016-03-16alpertronManual testing5000001500000012
skipped known factor: 20740833540599
---8.907%


Trial Factoring results:
5758596061626364656667
No TF results for M1912487


ECM factoring results:
Total ECM effort:39.532 GHz-days
Estimated T-Level:25.711
DigitsB1CompleteFacMiss
201100015.0110.000%
25500001.68318.575%
302500000.14286.740%
3510000000.01099.029%


ECM Summary

B1B2factorcurvesGHz-days
500005000000322.221
50000500000010.069
50000660000021016.45
50000675000070.554
250000400000004720.24


Lucas-Lehmer results:
No L-L results for M1912487


PRP results:
dateuseridcompidcofactorsres64
2017-10-04Oliver KruseGTX-3
20740833540599
3EB524C0E043E550
2017-11-09kkmrkkblmbrbkc4.large
20740833540599
3EB524C0E043E550
2018-05-03Oliver KruseGTX-1
20740833540599
1296619882810264000543
CFE350A0E7E43CD7
2018-05-05BattlemaxxWork-2
20740833540599
1296619882810264000543
CFE350A0E7E43CD7


CERT results:
No CERT results for M1912487


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
TF factor-bounds graph:
this exponent TF target: 61
TF double-checked to: 67
ECM T-Level=25.71 ~= 69-bit
250
260
270
280
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Last modified: 2024-02-09T03:30:02+00:00