is 2 6959861 - 1
has 2095127 decimal digits
takes 1.518 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L718EF3B347F8F4B6double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272137.407068.0556%1000000300000000.81574.5622%138.222869.5129%
Target2674.269365.6716%4500072000000.13752.2384%4.406866.4401%
Difference+5+133.1377+2.3839%+955000+22800000+0.6783+2.3238%+133.8159+3.0729%

Known prime factors:
No known factors for M6959861

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-09-16ANONYMOUSv4_computers35000463750---0.018--0.880%
2012-08-21NesowaEPC850001508750---0.051--1.566%
2019-05-03takahashivaio30000050000006---0.176--2.684%
2021-06-22takahashivaio10000003000000012---0.816--4.562%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-07-11ANONYMOUSv4_computers21261--0.044--
1998-07-29ANONYMOUSv4_computers21262--0.088--
2005-07-17ANONYMOUSv4_computers21263--0.229--
2014-02-09NesowaManual testing263264--0.282--
2014-02-16lycornManual testing264265--0.537--
2015-06-26VictordeHollanderManual testing265266--1.074--
2016-04-06Gordon SpenceManual testing266267--2.147--
2018-02-26-Anonymous-Manual testing267268--4.295--
2020-04-24TJAOIManual testing268269--8.590--
2021-08-02takahashiManual testing269270--17.18--
2021-08-13SRBaseManual testing270271--34.36--
2021-09-28SRBaseManual testing271272--68.72--


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_computers718EF3B347F8F4B61.518
2001-10-20ANONYMOUSv4_computers718EF3B347F8F4B61.518


PRP results:
No PRP results for M6959861


P-1 factor-bounds graph:
B1 = 1000000, B2 = 30000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 300000, B2 = 5000000 (P-1 stage 2)
B1 = 300000 (P-1 stage 1)
B1 = 85000, B2 = 1508750 (P-1 stage 2)
B1 = 85000 (P-1 stage 1)
B1 = 35000, B2 = 463750 (P-1 stage 2)
B1 = 35000 (P-1 stage 1)
103
104
105
106
103
104
105
106
107
108
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: 67.8
ECM T-Level=1.15 ~= -13-bit
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280
Last modified: 2023-06-05T21:50:05+00:00