is 2 2566171 - 1
has 772495 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-LEC0DA46887781D3Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26711.579167.1642%17500041125000.03923.5396%11.618368.3265%1.1623%
PrimeNet2590.029962.7119%110002000000.00212.6884%0.032163.7143%1.0024%
GPU722630.621965.0794%120001800000.00211.4799%0.624165.5962%0.5168%
Difference+4+10.9571+2.0848%+163000+3932500+0.0370+2.0598%+10.9942+2.7303%+2.7303%

Known prime factors (1 factor, 75.3 bits, 0.00293306% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2566171454681185868587538314072375.2678859136547575893
3 × 4457 × 182057 × 3639319
2015-08-1418205736393195,442.90.03730.0373

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--0.621%
2011-04-16T19:45:00James HeinrichWHS1750004112500---0.039--3.540%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.030--
2022-03-11T02:05:01LordJuliusManual testing21260--0.060--
2009-01-29T16:45:00Sturle Sundegilia.ifi260261--0.060--
2012-06-17T13:43:00Sebastian HornbostelManual testing261262--0.120--
2013-01-14T11:55:00dbaughManual testing262263--0.383--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.765--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.456--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.384 GHz-days
Estimated T-Level:0.750
DigitsB1CurvesCompleteFacMiss
201100015 / 1000.15086.006%
255000015 / 2800.05494.775%

New Calculation Method

Total ECM effort:1.384 GHz-days
Estimated T-Level:0.750
DigitsB1CompleteFacMiss
20110000.48461.639%
25500000.04495.721%
302500000.00399.731%


ECM Summary

B1B2factorcurvesGHz-days
500005000000121.108
50000500000030.277


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-04-13T00:00:00ANONYMOUSv4_computersEC0DA46887781D3E0.178


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-15T03:37:36Oliver KruseGTX-2
45468118586858753831407
45C4CDC2191E8F__no
2017-12-01T19:35:15kkmrkkblmbrbkc4.xlarge
45468118586858753831407
45C4CDC2191E8F__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)
102
103
104
105
106
102
103
104
105
106
107
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