is 2 2564459 - 1
has 771980 decimal digits
takes 0.178 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LA929523D4FF8886Cdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26711.586867.1642%32000001120000000.91808.7486%12.504870.0369%2.8727%
PrimeNet2590.029962.7119%110002000000.00212.6881%0.032163.7142%1.0023%
GPU722630.622465.0794%120001800000.00211.4797%0.624565.5961%0.5167%
Difference+4+10.9645+2.0848%+3188000+111820000+0.9159+7.2689%+11.8803+4.4408%+4.4408%

Known prime factors (1 factor, 90.0 bits, 0.00351134% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
256445912788007134035425761314378072890.047249331479544719290917
11 × 19 × 131 × 373 × 999133 × 24435847
2016-05-1499913324435847178,558,3090.22890.2501

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-23T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.293%
2003-11-08T00:00:00Team Prime Ribv4_computers15000198750---0.003--0.885%
2010-12-21T01:09:00Jocelyn LaroucheManual testing2000020000---0.002--0.316%
2011-01-03T22:20:00Jocelyn LaroucheManual testing3000030000---0.003--0.433%
2011-01-10T23:57:00Jocelyn LaroucheManual testing5000050000---0.005--0.620%
2011-04-16T07:56:00James HeinrichWHS1750004112500---0.039--3.539%
2016-05-14T07:08:10mikrMSI3200000112000000122890.0470.9180.3561.8368.749%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:16Mark RoseManual testing259260--0.030--
2009-02-01T03:33:00Sturle Sundegowin.ifi260261--0.060--
2012-06-17T11:43:00Sebastian HornbostelManual testing261262--0.120--
2013-01-23T08:30:00dbaughManual testing262263--0.383--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.766--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.457--
2015-11-08T21:03:01ramgeisManual testing265266--2.914--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.661 GHz-days
Estimated T-Level:0.900
DigitsB1CurvesCompleteFacMiss
201100018 / 1000.18083.451%
255000018 / 2800.06493.763%

New Calculation Method

Total ECM effort:1.661 GHz-days
Estimated T-Level:0.900
DigitsB1CompleteFacMiss
20110000.58155.954%
25500000.05294.888%
302500000.00399.677%


ECM Summary

B1B2factorcurvesGHz-days
500005000000181.661


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-07-04T00:00:00bezaharv4_computersA929523D4FF8886C0.178


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-15T02:48:02Oliver KruseGTX-0
1278800713403542576131437807
2978BAD9C580BD__no
2017-12-01T16:49:23storm5510HP-Z220-CMT
1278800713403542576131437807
2978BAD9C580BD__no


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 175000, B2 = 4112500 (P-1 stage 2)
B1 = 175000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 198750 (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
109
TF factor-bounds graph:
267
266
265
264
263
262
261
260
259
250
260
270
280
290
2100
Last modified: 2017-12-01T16:49:23+00:00