is 2 2245681 - 1
has 676018 decimal digits
takes 0.148 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L0E096984DDA83A07double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26713.231667.1642 %500000150000000.12305.1949 %13.354668.8700 %
Target2620.273664.5161 %110009500000.00591.6593 %0.279565.1049 %
Difference+5+12.9580+2.6481 %+489000+14050000+0.1171+3.5355%+13.0751+3.7650 %

Known prime factors (1 factor, 71.8 bits, 0.00319701% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
224568140960070065729897326412271.795911974364696720
24 × 5 × 13 × 23 × 7573 × 5034467
2015-12-0575735034467212.890.02680.0488

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-04-03ANONYMOUSv4_computers204820480012--0.0010.784%
2010-11-11JossManual testing3000030000--0.0030.942%
2011-01-06markrtiny10000020750006--0.0204.772%
2014-08-25ANONYMOUSManual testing128581128581--0.0122.082%
2015-12-05Alexander DubrovinManual testing1000000100000001222271.7950.1428.107%
2016-04-29alpertronManual testing5000001500000012
skipped known factor: 4096007006572989732641
---8.290%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2009-01-11Sturle Sundegibsy.ifi2602610.068
2012-05-03Sebastian HornbostelManual testing2612620.137
2013-12-04LaurVManual testing2622630.437
2015-03-10VictordeHollanderManual testing2632640.874
2015-03-10VictordeHollanderManual testing2642651.664
2015-10-26ramgeisManual testing2652663.328


ECM factoring results:
Total ECM effort:21.838 GHz-days
Estimated T-Level:21.721
DigitsB1CompleteFacMiss
20110003.6152.691%
25500000.34470.877%
302500000.02297.814%
3510000000.00199.895%


ECM Summary

B1B2factorcurvesGHz-days
50000465000070.584
500005000000221.748
50000450334505019.51


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-26ANONYMOUSv4_computers0E096984DDA83A070.148


PRP results:
dateuseridcompidcofactorsres64
2017-09-30alpertronManual testing
4096007006572989732641
D530BB4F6C8A3DEF
2017-10-29Oliver KruseGTX-1
4096007006572989732641
D530BB4F6C8A3DEF


CERT results:
No CERT results for M2245681


P-1 factor-bounds graph:
B1 = 1000000, B2 = 10000000 (P-1 stage 2)
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 500000 (P-1 stage 1)
B1 = 100000, B2 = 2075000 (P-1 stage 2)
B1 = 128581 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
103
104
105
106
102
103
104
105
106
107
108
TF factor-bounds graph:
266
265
264
263
262
261
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=21.72 ~= 56-bit
250
260
270
280
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Last modified: 2024-02-29T14:28:04+00:00