is 2 6902171 - 1
has 2077761 decimal digits
takes 1.505 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LEE649541ABF5267Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272138.555568.0556%40000004143239108.33317.9693%146.888670.6013%
Target2674.305065.6716%450009000000.02902.2353%4.334066.4390%
Difference+5+134.2505+2.3839%+3955000+413423910+8.3042+5.7340%+142.5546+4.1623%

Known prime factors:
No known factors for M6902171

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-08-24ANONYMOUSv4_computers35000341250---0.016--0.798%
2011-11-19James Heinrichi7-9201300002665000---0.085--1.985%
2020-01-07takahashivaio6000001200000012---0.386--3.580%
2021-11-20Seth_TrManual testing400000011000000012---3.091--6.529%
2021-11-29Seth_TrManual testing4000000414323910---8.333--7.969%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-07-11ANONYMOUSv4_computers21262--0.089--
2005-01-20ANONYMOUSv4_computers21263--0.231--
2014-02-09NesowaManual testing263264--0.284--
2014-02-17lycornManual testing264265--0.541--
2015-06-21VictordeHollanderManual testing265266--1.083--
2016-03-31Gordon SpenceManual testing266267--2.165--
2018-02-27-Anonymous-Manual testing267268--4.331--
2019-11-25mnd9Manual testing268269--8.661--
2020-12-20takahashiManual testing269270--17.32--
2021-08-10SRBaseManual testing270271--34.65--
2021-09-25SRBaseManual testing271272--69.29--


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)
1999-10-15ANONYMOUSv4_computersEE649541ABF5267E1.505
2001-10-27ANONYMOUSv4_computersEE649541ABF5267E1.505


PRP results:
No PRP results for M6902171


P-1 factor-bounds graph:
B1 = 4000000, B2 = 414323910 (P-1 stage 2)
B1 = 4000000, B2 = 110000000 (P-1 stage 2)
B1 = 4000000 (P-1 stage 1)
B1 = 600000, B2 = 12000000 (P-1 stage 2)
B1 = 600000 (P-1 stage 1)
B1 = 130000, B2 = 2665000 (P-1 stage 2)
B1 = 130000 (P-1 stage 1)
B1 = 35000, B2 = 341250 (P-1 stage 2)
B1 = 35000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
109
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: 2023-04-26T21:34:10+00:00