is 2 2853973 - 1
has 859132 decimal digits
takes 0.220 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L359CE8336BF00C9Adouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26710.411467.1642 %3600002960911801.84488.0388 %12.256269.8038 %
Target2630.559265.0794 %1600013000000.00961.8294 %0.568965.7182 %
Difference+4+9.8522+2.0848 %+344000+294791180+1.8351+6.2094%+11.6873+4.0856 %

Known prime factors (2 factors, 126.3 bits, 0.00442484% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
285397354956341159260588311962.253962804153355
3 × 5 × 11 × 89 × 65563783
2009-03-2689655637830.21530.40010.7472
2853973188429553362151559272064.0313301179677631
32 × 11 × 33345249269
2017-06-2911333452492691.2471203.46380.01

1 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-11-28ANONYMOUSv4_computers2048204800--0.0010.685%
2023-02-18USAFSS6917th_Scty_Sq360000296091180
skipped known factor: 5495634115926058831
--2.03311.333%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2009-02-14Sturle Sundegolan.ifi2602610.054
2022-03-10LordJuliusManual testing261262
2022-03-10LordJuliusManual testing263264
2017-06-29TJAOIManual testing264265*64.031200.040


ECM factoring results:
Total ECM effort:0.386 GHz-days
Estimated T-Level:0.577
DigitsB1CompleteFacMiss
20110000.11589.102%
25500000.01198.938%


ECM Summary

B1B2factorcurvesGHz-days
10.081
50000500000030.306


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-06-06ANONYMOUSv4_computers359CE8336BF00C9A0.220


PRP results:
dateuseridcompidcofactorsres64
2017-09-28alpertronManual testing
18842955336215155927
5495634115926058831
79205FA3F2D471BC
2017-11-16Oliver KruseThreadripper-PC
5495634115926058831
18842955336215155927
79205FA3F2D471BC


CERT results:
No CERT results for M2853973


P-1 factor-bounds graph:
B1 = 360000, B2 = 296091180 (P-1 stage 2)
B1 = 360000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
100
101
102
103
104
105
106
100
101
102
103
104
105
106
107
108
109
1010
1011
TF factor-bounds graph:
264
262
261
this exponent TF target: 63
TF double-checked to: 67
ECM T-Level=0.58 ~= -15-bit
250
260
270
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Last modified: 2024-02-09T03:30:02+00:00