is 2 1973761 - 1
has 594162 decimal digits
takes 0.130 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LD4B7D21B4E2EA24Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26715.054568.6567 %1000000300000000.24606.2443 %15.300470.6139 %
Target2620.311366.1290 %80005000000.00331.1964 %0.314666.5343 %
Difference+5+14.7432+2.5277 %+992000+29500000+0.2427+5.0479%+14.9859+4.0796 %

Known prime factors (1 factor, 71.8 bits, 0.00363618% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
197376140249823079370380523272271.7691019622514564083
3 × 114883 × 2958437467
2016-02-131148832958437467242.2215.37728.701

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2011-03-20kurlyhex10000003000000012--0.2469.649%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-12-27ANONYMOUSv4_computers212580.019
2016-02-23Mark RoseManual testing2582600.058
2009-12-29S485122USB-W2602610.078
2016-02-23Mark RoseManual testing2612620.156
2011-08-27GrunwalderGIMPManual testing212630.808
2016-02-23Mark RoseManual testing2622630.497
2015-03-19lycornManual testing2632640.995
2015-03-19lycornManual testing2642651.893
2015-09-10ramgeisManual testing2652663.786


ECM factoring results:
Total ECM effort:25.416 GHz-days
Estimated T-Level:25.328
DigitsB1CompleteFacMiss
201100010.9070.002%
25500001.03035.684%
302500000.06693.643%
3510000000.00399.691%


ECM Summary

B1B2factorcurvesGHz-days
500005000000392.718
50000500000030.209
50000708409570.570
50000750000021621.92


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-17ANONYMOUSv4_computersD4B7D21B4E2EA24E0.130
2015-07-12MadPooManual testingD4B7D21B4E2EA24E0.130


PRP results:
dateuseridcompidcofactorsres64
2017-09-30alpertronManual testing
4024982307937038052327
310668D54BDEE118
2017-10-20Oliver KruseGTX-0
4024982307937038052327
310668D54BDEE118


CERT results:
No CERT results for M1973761


P-1 factor-bounds graph:
B1 = 1000000, B2 = 30000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
104
105
106
104
105
106
107
108
109
1010
TF factor-bounds graph:
266
265
264
263
262
261
260
258
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=25.33 ~= 68-bit
250
260
270
280
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Last modified: 2024-02-29T14:28:04+00:00