is 2 2728247 - 1
has 821285 decimal digits
takes 0.211 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L30CFD28F95CE7CA9double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26710.891267.1642%2700000840000000.79848.3225%11.689769.8969%2.7328%
PrimeNet2590.028162.7119%120002200000.00262.8484%0.030863.7740%1.0621%
GPU722630.585065.0794%140002400000.00291.7064%0.587965.6753%0.5959%
Difference+4+10.3062+2.0848%+2686000+83760000+0.7955+6.6161%+11.1017+4.2217%+4.2217%

Known prime factors (1 factor, 99.2 bits, 0.00363613% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
27282477293331636399387871486720124073099.202133663331003376671384349
3 × 7 × 11 × 12421 × 59809 × 220333 × 3535067
2016-10-1622033335350676.941e+100.04490.0502

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-11-16T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.298%
2003-11-28T00:00:00Team Prime Ribv4_computers15000225000---0.003--0.932%
2010-12-19T21:42:00Jocelyn LaroucheManual testing2000020000---0.002--0.320%
2010-12-28T02:16:00Jocelyn LaroucheManual testing3000030000---0.003--0.439%
2011-01-19T23:50:00Jocelyn LaroucheManual testing5000050000---0.006--0.628%
2011-04-25T16:05:00James HeinrichWHS1850004578750---0.048--3.684%
2016-10-16T17:58:02mikrMSI270000084000000123099.2020.7980.4211.5978.322%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-01-13T00:00:00ANONYMOUSv4_computers21259--0.028--
2016-02-23T16:29:20Mark RoseManual testing259260--0.028--
2009-01-31T02:04:00Sturle Sundegoscha.ifi260261--0.056--
2012-04-15T13:09:00markroldgamer261262--0.113--
2013-01-14T12:26:00dbaughManual testing262263--0.360--
2015-04-13T20:09:00VictordeHollanderManual testing263264--0.720--
2015-04-13T20:09:00VictordeHollanderManual testing264265--1.370--
2016-02-01T09:40:54ramgeisManual testing265266--2.739--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.867 GHz-days
Estimated T-Level:0.900
DigitsB1CurvesCompleteFacMiss
201100018 / 1000.18083.451%
255000018 / 2800.06493.763%

New Calculation Method

Total ECM effort:1.867 GHz-days
Estimated T-Level:0.900
DigitsB1CompleteFacMiss
20110000.58155.954%
25500000.05294.888%
302500000.00399.677%


ECM Summary

B1B2factorcurvesGHz-days
500005000000181.867


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-01-13T00:00:00ANONYMOUSv4_computers30CFD28F95CE7CA90.211
1999-04-13T00:00:00S00030v4_computers30CFD28F95CE7CA90.211


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-20T01:48:02Oliver KruseGTX-2
729333163639938787148672012407
6017177A3B72BA__no
2017-12-05T06:25:59kkmrkkblmbrbkc4.xlarge
729333163639938787148672012407
6017177A3B72BA__no


P-1 factor-bounds graph:
B1 = 2700000, B2 = 84000000 (P-1 stage 2)
B1 = 2700000 (P-1 stage 1)
B1 = 185000, B2 = 4578750 (P-1 stage 2)
B1 = 185000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 225000 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
103
104
105
106
107
102
103
104
105
106
107
108
TF factor-bounds graph:
267
266
265
264
263
262
261
260
259
250
260
270
280
290
2100
Last modified: 2017-12-05T06:25:59+00:00