is 2 2971747 - 1
has 894585 decimal digits
takes 0.253 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LA74802729676A751double-checked
PRP99EAA064CF616863verified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26820.057267.6471%1000000200000000.25125.5483%20.308369.4421%1.7951%
PrimeNet2600.051763.3333%120002200000.00292.5107%0.054664.2539%0.9206%
GPU722641.197765.6250%120002000000.00271.3486%1.200566.0886%0.4636%
Difference+4+18.8595+2.0221%+988000+19800000+0.2484+4.1997%+19.1079+3.3535%+3.3535%

Known prime factors (1 factor, 76.8 bits, 0.00258575% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
29717471354241652841732049654392476.84222785278370630677
11 × 53 × 349 × 367 × 305136593
2020-11-173673051365937,442.82.05173.8319

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-12-13T00:00:00ANONYMOUSv4_computers2048204800---0.002--0.247%
2003-12-23T00:00:00Team Prime Ribv4_computers1000010000---0.001--0.146%
2010-10-27T20:58:00markrtiny950001995000---0.024--2.459%
2015-05-08T13:54:00VictordeHollanderManual testing100000020000000---0.251--5.548%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-05-02T00:00:00Nayan Hajratwalav4_computers21260--0.052--
2009-02-12T22:01:00Sturle Sundeantonov.ifi260261--0.052--
2011-11-29T06:57:00Sebastian HornbostelManual testing261262--0.103--
2013-01-07T13:51:00dbaughManual testing262263--0.330--
2015-04-29T14:58:00VictordeHollanderManual testing263264--0.661--
2015-04-29T14:58:00VictordeHollanderManual testing264265--1.257--
2016-02-28T22:17:41ramgeisManual testing265266--2.515--
2017-12-03T16:23:23Gordon SpenceManual testing266267--5.029--
2018-12-25T13:40:43chuenkitManual testing267268--10.06--


ECM factoring results:

Old Calculation Method

Total ECM effort:4.174 GHz-days
Estimated T-Level:1.800
DigitsB1CurvesCompleteFacMiss
201100036 / 1000.36069.641%
255000036 / 2800.12987.915%

New Calculation Method

Total ECM effort:4.174 GHz-days
Estimated T-Level:1.800
DigitsB1CompleteFacMiss
20110001.16131.308%
25500000.10590.036%
302500000.00699.356%


ECM Summary

B1B2factorcurvesGHz-days
500005000000323.710
50000500000040.464


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-06-15T00:00:00Nayan Hajratwalav4_computersA74802729676A7510.253
2018-10-18T04:12:56kkmrkkblmbrbkoldA74802729676A7510.253


PRP results:
dateuseridcompidcofactorsres64PRP
2020-12-13T01:36:19Kirill Frolovshodan1
135424165284173204965439
99EAA064CF616863no


P-1 factor-bounds graph:
B1 = 1000000, B2 = 20000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 95000, B2 = 1995000 (P-1 stage 2)
B1 = 95000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 10000 (P-1 stage 1)
B1 = 2048 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2020-12-13T01:36:19+00:00