is 2 6983261 - 1
has 2102172 decimal digits
takes 1.523 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L076082969D4AB44Adouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272136.946668.0556%2000000580000001.59705.5234%138.543669.8200%
Target2674.255065.6716%450009000000.02902.2397%4.284066.4405%
Difference+5+132.6916+2.3839%+1955000+57100000+1.5681+3.2837%+134.2596+3.3795%

Known prime factors:
No known factors for M6983261

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-09-22ANONYMOUSv4_computers2500087500---0.009--0.432%
2011-06-23Carsten Kossendeyleela44500013572500---0.367--3.528%
2021-11-07Seth_TrManual testing20000005800000012---1.597--5.523%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-07-11WanderingShoev4_computers21262--0.088--
2000-12-14ANONYMOUSv4_computers21262--0.088--
2004-07-26Sturle Sundev4_computers21263--0.229--
2014-02-09NesowaManual testing263264--0.281--
2014-02-14lycornManual testing264265--0.535--
2015-07-03VictordeHollanderManual testing265266--1.070--
2016-04-26Gordon SpenceManual testing266267--2.140--
2018-02-26-Anonymous-Manual testing267268--4.280--
2020-04-10TJAOIManual testing268269--8.561--
2021-08-11takahashiManual testing269270--17.12--
2021-09-06SRBaseManual testing270271--34.24--
2021-09-28SRBaseManual testing271272--68.49--


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)
1999-03-26ANONYMOUSv4_computers84D5D8F08C3ACD__1.523
1999-05-23curtiscv4_computers076082969D4AB44A1.523
2001-12-08ANONYMOUSv4_computers076082969D4AB44A1.523


PRP results:
No PRP results for M6983261


P-1 factor-bounds graph:
B1 = 2000000, B2 = 58000000 (P-1 stage 2)
B1 = 2000000 (P-1 stage 1)
B1 = 445000, B2 = 13572500 (P-1 stage 2)
B1 = 445000 (P-1 stage 1)
B1 = 25000, B2 = 87500 (P-1 stage 2)
B1 = 25000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
TF factor-bounds graph:
272
271
270
269
268
267
266
265
264
263
262
this exponent TF target: 67
TF double-checked to: 67.8
ECM T-Level=1.15 ~= -13-bit
250
260
270
280
Last modified: 2023-03-25T13:08:14+00:00