is 2 2565257 - 1
has 772220 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-L333761F0C26C0EF6double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26711.583267.1642%17500041125000.03923.5395%11.622468.3264%1.1622%
PrimeNet2590.029962.7119%110002000000.00212.6882%0.032163.7142%1.0024%
GPU722630.622265.0794%120001800000.00211.4798%0.624365.5961%0.5167%
Difference+4+10.9610+2.0848%+163000+3932500+0.0370+2.0597%+10.9981+2.7303%+2.7303%

Known prime factors (1 factor, 76.4 bits, 0.00297686% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2565257972474652580365840313992376.36418954721740947707
11 × 13 × 181 × 732323213729
2015-08-1318173232321372910,4694,012.87,494.8

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%
2011-04-14T15:06:00James HeinrichWHS1750004112500---0.039--3.539%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.030--
2022-03-11T02:05:01LordJuliusManual testing21260--0.060--
2009-01-29T01:30:00Sturle Sundegilia.ifi260261--0.060--
2012-06-17T12:42:00Sebastian HornbostelManual testing261262--0.120--
2013-10-14T18:52:00lycornsnail262263--0.383--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.765--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.457--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.292 GHz-days
Estimated T-Level:0.700
DigitsB1CurvesCompleteFacMiss
201100014 / 1000.14086.875%
255000014 / 2800.05095.114%

New Calculation Method

Total ECM effort:1.292 GHz-days
Estimated T-Level:0.700
DigitsB1CompleteFacMiss
20110000.45263.660%
25500000.04196.001%
302500000.00399.749%


ECM Summary

B1B2factorcurvesGHz-days
500005000000121.107
50000500000020.185


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-04-02T00:00:00ANONYMOUSv4_computers333761F0C26C0EF60.178


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-15T04:48:39Oliver KruseGTX-1
97247465258036584031399
A8F3CC282A39EF__no
2017-12-02T04:00:07kkmrkkblmbrbkold
97247465258036584031399
A8F3CC282A39EF__no


P-1 factor-bounds graph:
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)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
1010
1011
1012
TF factor-bounds graph:
267
265
264
263
262
261
260
259
250
260
270
280
290
2100
Last modified: 2022-03-11T02:05:01+00:00