is 2 2553233 - 1
has 768600 decimal digits
takes 0.177 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LBB3C0C850C961E28double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26711.637867.1642%2000000600000000.51907.6637%12.156769.6806%2.5164%
PrimeNet2590.030162.7119%110002000000.00212.6859%0.032263.7134%1.0015%
GPU722630.625165.0794%120001800000.00211.4784%0.627265.5956%0.5163%
Difference+4+11.0127+2.0848%+1988000+59820000+0.5168+6.1853%+11.5295+4.0850%+4.0850%

Known prime factors (1 factor, 68.5 bits, 0.00268334% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
25532334208423763133982618812168.51282413625453180
22 × 5 × 7 × 23 × 1201 × 21310819
2015-08-1012012131081941.7920.11690.2181

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--0.884%
2010-12-19T21:44:00Jocelyn LaroucheManual testing2000020000---0.002--0.315%
2011-01-03T14:35:00Jocelyn LaroucheManual testing3000030000---0.003--0.433%
2011-01-09T14:30:00Jocelyn LaroucheManual testing5000050000---0.005--0.620%
2011-04-09T06:24:00James HeinrichWHS1750004068750---0.039--3.529%
2019-07-04T12:40:31alpertronManual testing20000006000000012-
skipped known factor: 420842376313398261881
--0.519--7.664%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.030--
2022-03-11T02:04:59LordJuliusManual testing21260--0.060--
2009-01-31T01:47:00Sturle Sundegoomba.ifi260261--0.060--
2012-06-16T16:43:00Sebastian HornbostelManual testing261262--0.120--
2013-01-14T11:53:00dbaughManual testing262263--0.384--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.769--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.463--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.291 GHz-days
Estimated T-Level:0.700
DigitsB1CurvesCompleteFacMiss
201100014 / 1000.14086.875%
255000014 / 2800.05095.114%

New Calculation Method

Total ECM effort:1.291 GHz-days
Estimated T-Level:0.700
DigitsB1CompleteFacMiss
20110000.45263.660%
25500000.04196.001%
302500000.00399.749%


ECM Summary

B1B2factorcurvesGHz-days
500005000000121.107
50000500000020.184


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-05-02T00:00:00ANONYMOUSv4_computersBB3C0C850C961E280.177


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-14T22:20:56Oliver KruseGTX-10D763F5B213054__no
2017-12-01T10:55:58ATHec2-1xf
420842376313398261881
0D763F5B213054__no


P-1 factor-bounds graph:
B1 = 2000000, B2 = 60000000 (P-1 stage 2)
B1 = 2000000 (P-1 stage 1)
B1 = 175000, B2 = 4068750 (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
TF factor-bounds graph:
267
265
264
263
262
261
260
259
250
260
270
280
290
2100
Last modified: 2022-03-11T02:04:59+00:00