is 2 2238947 - 1
has 673991 decimal digits
takes 0.147 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L7839C75D6CAA7AADdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26713.271467.1642%500000150000000.12305.1930%13.394468.8693%1.7052%
PrimeNet2580.017162.0690%100001800000.00182.8723%0.019063.1585%1.0895%
GPU722620.274464.5161%110001900000.00201.6583%0.276465.1046%0.5884%
Difference+5+12.9970+2.6481%+489000+14810000+0.1210+3.5347%+13.1180+3.7648%+3.7648%

Known prime factors (1 factor, 62.4 bits, 0.00278688% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
223894760717653991151606971962.3971355942190484
22 × 7 × 79 × 612993757
2009-12-25796129937570.54813.18405.9469

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-03-27T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.282%
2016-04-22T15:30:29alpertronManual testing5000001500000012---0.123--5.193%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-02-07T00:00:00ANONYMOUSv4_computers21258--0.017--
2022-03-09T16:36:48LordJuliusManual testing21260--0.069--
2009-01-11T05:58:00Sturle Sundegoscha.ifi260261--0.069--


ECM factoring results:

Old Calculation Method

Total ECM effort:0.965 GHz-days
Estimated T-Level:0.500
DigitsB1CurvesCompleteFacMiss
201100010 / 1000.10090.438%
255000010 / 2800.03696.485%

New Calculation Method

Total ECM effort:0.965 GHz-days
Estimated T-Level:0.500
DigitsB1CompleteFacMiss
20110000.40766.561%
25500000.03896.269%
302500000.00299.759%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
50000500000030.257
50000715000070.707


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-02-21T00:00:00ANONYMOUSv4_computers7839C75D6CAA7AAD0.147


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-10T09:24:13Oliver KruseGTX-1
6071765399115160697
81C90497CBBEC1__no
2017-11-21T00:17:29kkmrkkblmbrbkold
6071765399115160697
81C90497CBBEC1__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (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
TF factor-bounds graph:
267
261
260
258
250
260
270
280
290
2100
Last modified: 2022-07-05T13:05:23+00:00