is 2 1897601 - 1
has 571235 decimal digits
takes 0.103 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L132A3E4B2D178FA3double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26715.658768.6567 %3300005810689502.51498.2421 %18.173571.2400 %
Target2610.161965.5738 %100008000000.00421.7269 %0.166166.1683 %
Difference+6+15.4968+3.0829 %+320000+580268950+2.5107+6.5151%+18.0075+5.0718 %

Known prime factors (1 factor, 68.5 bits, 0.00360932% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
18976014146611963467264991512168.490109259321729575
52 × 743 × 5882063081
2013-10-28743588206308131.41125.20947.083

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2012-01-23markrtiny275000600000012--0.0467.193%
2023-08-15Kevin_9611Factor_2330000581068950--3.04813.609%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2003-01-09ANONYMOUSv4_computers212580.020
2010-04-11Architects CubedManual testing2602610.081
2011-03-08GrunwalderGIMPManual testing212630.841


ECM factoring results:
Total ECM effort:81.623 GHz-days
Estimated T-Level:25.892
DigitsB1CompleteFacMiss
201100016.1630.000%
25500001.96913.964%
302500000.17883.655%
3510000000.01398.682%


ECM Summary

B1B2factorcurvesGHz-days
10.069
500005000000402.667
50000660000021016.43
2500002017994084762.46


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-10ANONYMOUSv4_computers132A3E4B2D178FA30.103


PRP results:
dateuseridcompidcofactorsres64
2017-10-04Oliver KruseGTX-2
414661196346726499151
C291949D58AF3271
2017-11-09kkmrkkblmbrbkold
414661196346726499151
C291949D58AF3271


CERT results:
No CERT results for M1897601


P-1 factor-bounds graph:
B1 = 330000, B2 = 581068950 (P-1 stage 2)
B1 = 275000, B2 = 6000000 (P-1 stage 2)
B1 = 330000 (P-1 stage 1)
B1 = 275000 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
263
261
258
this exponent TF target: 61
TF double-checked to: 67
ECM T-Level=25.89 ~= 69-bit
250
260
270
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Last modified: 2024-02-29T14:28:04+00:00