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
factored, 0 LL tests remaining
ResidueStatus
L-LB4B92A758EF351BBdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual27063.756868.5714 %1600000660000000.77806.1482 %64.534870.5037 %
Target2640.949765.6250 %2200022500000.02182.1105 %0.971566.3505 %
Difference+6+62.8071+2.9464 %+1578000+63750000+0.7562+4.0378%+63.5632+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
2021-08-133213440741303541127.56111,520208,289

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2009-07-07Carsten Kossendeymother20000265000--0.0051.781%
2013-03-15Squeeky_SquirrelT7500_220011000020350006--0.0334.149%
2015-11-22mikrMSI16000006600000012--0.77810.148%
2022-03-03JossManual testing9000090000--0.0141.461%
2022-03-22JossManual testing100000100000--0.0151.543%
2022-05-25JossManual testing100000130364850--1.3028.117%


Trial Factoring results:
5758596061626364656667686970
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1997-12-13ANONYMOUSv4_computers212600.020
2009-03-05S485122USB-A2602610.041
2011-05-04markrManual testing212620.082
2012-05-10GrunwalderGIMPManual testing212630.426
2016-02-23Mark RoseManual testing2622630.262
2015-01-23VictordeHollanderManual testing2632640.524
2015-01-23VictordeHollanderManual testing2642650.997
2016-02-26ramgeisManual testing2652661.994
2016-11-06Gordon SpenceManual testing2662673.988
2018-06-18TJAOIManual testing2672687.976
2020-12-09axnManual testing26826915.95
2021-03-21axnManual testing26927031.90


ECM factoring results:
Total ECM effort:2.865 GHz-days
Estimated T-Level:3.766
DigitsB1CompleteFacMiss
20110000.75347.085%
25500000.07093.264%
302500000.00499.560%


ECM Summary

B1B2factorcurvesGHz-days
500005000000121.644
50000680000071.220


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


PRP results:
dateuseridcompidcofactorsres64
2021-08-15/r/counting
3223925886224142478529
96A380D5D118AA65
2021-08-16kutensryzen2
3223925886224142478529
96A380D5D118AA65


CERT results:
dateuseridcompid
2021-08-15ky0urakudb1-2
2021-08-16Simon Josefssonmorot


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)
100
101
102
103
104
105
106
107
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
1013
1014
TF factor-bounds graph:
270
269
268
267
266
265
264
263
262
261
260
this exponent TF target: 64
TF double-checked to: 67
ECM T-Level=3.77 ~= -4-bit
250
260
270
280
JSON version of this page
Last modified: 2024-02-09T03:30:02+00:00