is 2 1975957 - 1
has 594823 decimal digits
takes 0.130 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
Actual26715.037768.6567 %3840004031609402.12878.0969 %17.166571.1946 %
Target2620.310966.1290 %80005000000.00331.1967 %0.314266.5344 %
Difference+5+14.7268+2.5277 %+376000+402660940+2.1254+6.9003%+16.8522+4.6602 %

Known prime factors (3 factors, 147.9 bits, 0.00748475% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1975957707392607929.398179
179
-11793.760e-111.020e-61.741e-6
19759571526518743538791547.11738627327
23 × 1049 × 1601
2014-02-26104916011.796e-50.00010.0002
197595730733670122428383621272271.380777690762562859
777690762562859
2021-12-041777690762562859257.614,039,5207,544,699

4 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2022-08-13USAFSS6917th_Scty_Sq384000403160940
skipped known factor: 707392607
skipped known factor: 152651874353879
--2.12912.352%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2014-02-26TJAOIManual testing??
47.117
15


ECM factoring results:
Total ECM effort:25.657 GHz-days
Estimated T-Level:25.329
DigitsB1CompleteFacMiss
201100010.9130.002%
25500001.03135.662%
302500000.06693.636%
3510000000.00399.691%


ECM Summary

B1B2factorcurvesGHz-days
500005000000201.457
50000527227470.604
50000675000070.557
50000675000070.557
50000683505270.560
50000750000021621.92


Lucas-Lehmer results:
No L-L results for M1975957


PRP results:
dateuseridcompidcofactorsres64
2017-10-05Oliver KruseGTX-2
707392607
152651874353879
2D42B339837A385D
2017-11-12Chang Chia-Tcheex01
707392607
152651874353879
2D42B339837A385D
2021-12-08SRJ2877LTOS
707392607
152651874353879
3073367012242838362127
FF34A5C0B9A4D8C6


CERT results:
dateuseridcompid
2021-12-10LOBESLENOVO


P-1 factor-bounds graph:
B1 = 384000, B2 = 403160940 (P-1 stage 2)
B1 = 384000 (P-1 stage 1)
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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