is 2 6987373 - 1
has 2103409 decimal digits
takes 1.524 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L5A884D558A1C1EE3double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272136.866068.0556 %35000009616446840166.703011.3036 %303.569071.6664 %
Target2674.252565.6716 %4500045000000.09102.2399 %4.343566.4406 %
Difference+5+132.6135+2.3839 %+3455000+9611946840+166.6120+9.0637%+299.2255+5.2259 %

Known prime factors:
No known factors for M6987373

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2001-09-22ANONYMOUSv4_computers3000030000--0.0090.538%
2011-09-07Carsten Kossendeymother4450001368375012--0.3695.771%
2021-11-05Seth_TrManual testing20000005800000012--1.5978.438%
2023-09-21ThaZ-17035000009616446840--199.615.804%


Trial Factoring results:
57585960616263646566676869707172
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-07-11ANONYMOUSv4_computers212610.022
1998-10-25Mike Curtisv4_computers212620.044
2005-08-16David Campeauv4_computers212630.140
2014-02-09NesowaManual testing2632640.281
2014-02-14lycornManual testing2642650.535
2015-07-03VictordeHollanderManual testing2652661.069
2016-04-27Gordon SpenceManual testing2662672.139
2018-02-26ANONYMOUSManual testing2672684.278
2020-04-10TJAOIManual testing2682698.556
2021-08-12takahashiManual testing26927017.11
2021-09-06SRBaseManual testing27027134.22
2021-09-26SRBaseManual testing27127268.45


ECM factoring results:
Total ECM effort:1.989 GHz-days
Estimated T-Level:1.154
DigitsB1CompleteFacMiss
20110000.23179.392%
25500000.02197.887%
302500000.00199.865%


ECM Summary

B1B2factorcurvesGHz-days
50000500000061.989


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-09-22ANONYMOUSv4_computers5A884D558A1C1EE31.524
2001-11-24ANONYMOUSv4_computers5A884D558A1C1EE31.524


PRP results:
No PRP results for M6987373


CERT results:
No CERT results for M6987373


P-1 factor-bounds graph:
B1 = 3500000, B2 = 9616446840 (P-1 stage 2)
B1 = 2000000, B2 = 58000000 (P-1 stage 2)
B1 = 3500000 (P-1 stage 1)
B1 = 2000000 (P-1 stage 1)
B1 = 445000, B2 = 13683750 (P-1 stage 2)
B1 = 445000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
103
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106
107
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104
105
106
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1010
TF factor-bounds graph:
272
271
270
269
268
267
266
265
264
263
262
261
this exponent TF target: 67
TF double-checked to: 67
ECM T-Level=1.15 ~= -13-bit
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Last modified: 2024-03-13T02:15:48+00:00