is 2 2047729 - 1
has 616428 decimal digits
takes 0.135 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
Actual26714.510768.6567%500000150000000.12305.1376%14.633770.2670%
Target2620.300066.1290%90006000000.00391.3300%0.303966.5795%
Difference+5+14.2106+2.5277%+491000+14400000+0.1191+3.8076%+14.3297+3.6875%

Known prime factors (2 factors, 80.4 bits, 0.00392795% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
20477293983692951191238.53597271
211 × 461
-2114611.885e-82.141e-54.094e-5
204772940993363987271341.8991000947
3 × 109 × 3061
2008-07-1510930612.368e-72.573e-52.969e-5

1 Composite Factors:
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-17alpertronManual testing5000001500000012-
skipped known factor: 398369295119
skipped known factor: 4099336398727
--0.123--5.138%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2008-07-15J FeitsmaManual testing??41.899139.37328e-80.5713.97333e-7


ECM factoring results:
Total ECM effort:12.945 GHz-days
Estimated T-Level:22.212
DigitsB1CompleteFacMiss
20110004.5591.048%
25500000.44264.245%
302500000.03097.081%
3510000000.00199.852%


ECM Summary

B1B2factorcurvesGHz-days
500005000000201.697
500006750000141.356
50000687853070.684
50000700000070.690
500002702353571.656
6775910009194506.861


Lucas-Lehmer results:
No L-L results for M2047729


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-06Oliver KruseGTX-0
398369295119
4099336398727
88A2FD03DA94AF__no
2017-11-15kkmrkkblmbrbkc4.xlarge
398369295119
4099336398727
88A2FD03DA94AF__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
TF factor-bounds graph:
2
this exponent TF target: 62
TF double-checked to: 67.9
ECM T-Level=22.21 ~= 57-bit
250
260
270
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Last modified: 2023-11-06T20:15:09+00:00