is 2 1968427 - 1
has 592556 decimal digits
takes 0.129 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
Actual26715.095368.6567 %500000196403361010.246810.0575 %25.342071.8091 %
Target2620.312166.1290 %80005000000.00331.1957 %0.315466.5340 %
Difference+5+14.7832+2.5277 %+492000+1963533610+10.2434+8.8618%+25.0266+5.2750 %

Known prime factors (2 factors, 133.2 bits, 0.00676760% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1968427626024232299991445.83115901637
15901637
-1159016374.555e-60.08260.1543
19684272019389079980610637958513832787.38451294487425254038833
3 × 7 × 1109 × 211441 × 10416711817
2022-04-072114411041671181725,548,91654.126101.06

1 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2022-04-12Lisander ViaeneDesktop5000001964033610
skipped known factor: 62602423229999
--10.5314.828%


Trial Factoring results:
5758596061626364656667
No TF results for M1968427


ECM factoring results:
Total ECM effort:25.246 GHz-days
Estimated T-Level:25.325
DigitsB1CompleteFacMiss
201100010.7970.002%
25500001.02036.067%
302500000.06593.703%
3510000000.00399.694%


ECM Summary

B1B2factorcurvesGHz-days
500005000000130.906
50000500000040.279
500005626755141.024
50000675000070.556
50000712129970.571
50000750000021621.91


Lucas-Lehmer results:
No L-L results for M1968427


PRP results:
dateuseridcompidcofactorsres64
2017-10-05Oliver KruseGTX-0
62602423229999
1A97A2EC04C05D57
2017-11-12Chang Chia-Tcheex01
62602423229999
1A97A2EC04C05D57
2022-04-09_p95holder_TFL16_PRPt11-E_b
62602423229999
201938907998061063795851383
47320AAD20AC2BD5
2022-04-12ATHec2-PRPCF
62602423229999
201938907998061063795851383
47320AAD20AC2BD5


CERT results:
dateuseridcompid
2022-04-12Sharks_w_Lasersgear-05


P-1 factor-bounds graph:
B1 = 500000, B2 = 1964033610 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
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106
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101
102
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104
105
106
107
108
109
1010
1011
TF factor-bounds graph:
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=25.33 ~= 68-bit
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Last modified: 2024-03-13T02:15:48+00:00