is 2 2724047 - 1
has 820020 decimal digits
takes 0.210 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LD33CE1688BB4A8F1double-checked
PRPECCF9C5676B86ECFverified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26821.881067.6471%60000060000000.10014.0831%21.981168.9681%1.3210%
PrimeNet2590.028262.7119%120002200000.00262.8476%0.030863.7737%1.0618%
GPU722630.585965.0794%140002400000.00291.7059%0.588865.6751%0.5957%
Difference+5+21.2951+2.5677%+586000+5760000+0.0972+2.3772%+21.3923+3.2930%+3.2930%

Known prime factors (1 factor, 73.5 bits, 0.00269743% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2724047131651175307917496108312373.4792416462992523945
5 × 483292598504789
2021-01-2054832925985047891,225.92,948,8845,507,693

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-11-16T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.241%
2003-11-28T00:00:00Team Prime Ribv4_computers15000221250---0.003--0.793%
2010-12-19T21:42:00Jocelyn LaroucheManual testing2000020000---0.002--0.269%
2010-12-28T02:15:00Jocelyn LaroucheManual testing3000030000---0.003--0.372%
2011-01-18T22:18:00Jocelyn LaroucheManual testing5000050000---0.006--0.538%
2011-02-24T13:33:00James Heinrichi7-9203000008000000---0.081--3.994%
2018-08-20T10:32:22Jocelyn Larouchelow 4M60000060000006---0.100--4.083%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-06-07T00:00:00BJBv4_computers21259--0.028--
2016-02-23T16:29:20Mark RoseManual testing259260--0.028--
2009-01-28T20:06:00Sturle Sundegimo.ifi260261--0.056--
2012-04-18T10:21:00Grant McCrackenthumper261262--0.113--
2013-01-14T12:26:00dbaughManual testing262263--0.360--
2015-04-13T20:09:00VictordeHollanderManual testing263264--0.721--
2015-04-13T20:09:00VictordeHollanderManual testing264265--1.372--
2016-01-31T12:58:56ramgeisManual testing265266--2.743--
2017-10-05T11:09:27Gordon SpenceManual testing266267--5.486--
2019-02-12T09:01:42chuenkitManual testing267268--10.97--


ECM factoring results:

Old Calculation Method

Total ECM effort:8.034 GHz-days
Estimated T-Level:3.850
DigitsB1CurvesCompleteFacMiss
201100077 / 1000.77046.122%
255000077 / 2800.27575.920%

New Calculation Method

Total ECM effort:8.034 GHz-days
Estimated T-Level:3.850
DigitsB1CompleteFacMiss
20110002.4918.286%
25500000.22579.833%
302500000.01498.622%


ECM Summary

B1B2factorcurvesGHz-days
500005000000747.676
50000675000030.358


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-07-21T00:00:00ANONYMOUSv4_computersD33CE1688BB4A8F10.210
1998-09-27T00:00:00ANONYMOUSv4_computersD33CE1688BB4A8F10.210
1999-05-23T00:00:00ANONYMOUSv4_computersD33CE1688BB4A8F10.210


PRP results:
dateuseridcompidcofactorsres64PRP
2021-01-20T13:13:39riccardo ubertiColab_noGPU12
13165117530791749610831
ECCF9C5676B86ECFno


P-1 factor-bounds graph:
B1 = 600000, B2 = 6000000 (P-1 stage 2)
B1 = 300000, B2 = 8000000 (P-1 stage 2)
B1 = 600000 (P-1 stage 1)
B1 = 300000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 221250 (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)
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TF factor-bounds graph:
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Last modified: 2021-01-20T13:13:39+00:00