is 2 3747847 - 1
has 1128215 decimal digits
takes 0.394 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LB4B92A758EF351BBdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual27063.756868.5714%1600000660000000.77806.1482%64.534870.5037%1.9323%
PrimeNet2600.041063.3333%160003200000.00503.0905%0.045964.4665%1.1332%
GPU722640.949765.6250%220004500000.00692.1105%0.956666.3505%0.7255%
Difference+6+62.8071+2.9464%+1578000+65550000+0.7711+4.0378%+63.5782+4.1533%+4.1533%

Known prime factors (1 factor, 71.4 bits, 0.00190641% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
374784732239258862241424785292271.449430103721713312
25 × 13440741303541
2021-08-133213440741303541241.14111,520208,289

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2009-07-07T04:45:00Carsten Kossendeyleela20000265000---0.005--0.730%
2013-03-15T01:17:00Squeeky_SquirrelT7500_22001100002035000---0.033--2.076%
2015-11-22T02:04:08mikrMSI16000006600000012---0.778--6.148%
2022-03-03T20:39:05Jocelyn LaroucheManual testing9000090000---0.014--0.624%
2022-03-22T11:09:13Jocelyn LaroucheManual testing100000100000---0.015--0.666%
2022-05-25T14:13:59Jocelyn LaroucheManual testing100000130364850---1.096--4.379%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1997-12-13T00:00:00ANONYMOUSv4_computers21260--0.041--
2009-03-05T06:53:00S485122USB-A260261--0.041--
2011-05-04T20:59:00markrManual testing21262--0.164--
2012-05-10T01:22:00GrunwalderGIMPManual testing21263--0.426--
2016-02-23T16:29:38Mark RoseManual testing262263--0.262--
2015-01-23T13:17:00VictordeHollanderManual testing263264--0.524--
2015-01-23T13:17:00VictordeHollanderManual testing264265--0.997--
2016-02-26T10:03:31ramgeisManual testing265266--1.994--
2016-11-06T04:15:34Gordon SpenceManual testing266267--3.988--
2018-06-18T10:07:26TJAOIManual testing267268--7.976--
2020-12-09T13:21:03axnManual testing268269--15.95--
2021-03-21T08:32:38axnManual testing269270--31.90--


ECM factoring results:

Old Calculation Method

Total ECM effort:3.014 GHz-days
Estimated T-Level:0.950
DigitsB1CurvesCompleteFacMiss
201100019 / 1000.19082.617%
255000019 / 2800.06893.428%

New Calculation Method

Total ECM effort:3.014 GHz-days
Estimated T-Level:0.950
DigitsB1CompleteFacMiss
20110000.75347.085%
25500000.07093.264%
302500000.00499.560%


ECM Summary

B1B2factorcurvesGHz-days
500005000000121.793
50000680000071.220


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-01-05T00:00:00ANONYMOUSv4_computersB4B92A758EF351BB0.394
1999-11-04T00:00:00ANONYMOUSv4_computersB4B92A758EF351BB0.394


PRP results:
dateuseridcompidcofactorsres64PRP
2021-08-15T10:58:43GURA LOVE
3223925886224142478529
96A380D5D118AA65no
2021-08-16T07:16:30kutensryzen2
3223925886224142478529
96A380D5D118AA65no


P-1 factor-bounds graph:
B1 = 100000, B2 = 130364850 (P-1 stage 2)
B1 = 1600000, B2 = 66000000 (P-1 stage 2)
B1 = 1600000 (P-1 stage 1)
B1 = 110000, B2 = 2035000 (P-1 stage 2)
B1 = 110000 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 90000 (P-1 stage 1)
B1 = 20000, B2 = 265000 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-05-25T14:13:59+00:00