is 2 6958937 - 1
has 2094849 decimal digits
takes 1.517 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L23677EC1D28D98FCdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272137.425268.0556%20000002588493605.05696.9818%142.482270.2859%
Target2674.269965.6716%450009000000.02902.2384%4.298866.4400%
Difference+5+133.1554+2.3839%+1955000+257949360+5.0280+4.7435%+138.1833+3.8458%

Known prime factors:
No known factors for M6958937

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-10-20ANONYMOUSv4_computers35000288750---0.015--0.756%
2011-12-13James HeinrichQ66001300002827500---0.088--2.016%
2020-01-23takahashivaio6000001200000012---0.386--3.584%
2021-12-07Seth_TrManual testing2000000258849360---5.057--6.982%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-07-21Roger Varnesv4_computers21262--0.088--
2000-02-01ANONYMOUSv4_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--2.148--
2018-02-25-Anonymous-Manual testing267268--4.295--
2020-04-24TJAOIManual testing268269--8.591--
2021-08-01takahashiManual testing269270--17.18--
2021-08-12SRBaseManual testing270271--34.36--
2021-09-25SRBaseManual testing271272--68.73--


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)
2000-04-27ANONYMOUSv4_computers23677EC1D28D98FC1.517
2002-01-15ANONYMOUSv4_computers23677EC1D28D98FC1.517


PRP results:
No PRP results for M6958937


P-1 factor-bounds graph:
B1 = 2000000, B2 = 258849360 (P-1 stage 2)
B1 = 2000000 (P-1 stage 1)
B1 = 600000, B2 = 12000000 (P-1 stage 2)
B1 = 600000 (P-1 stage 1)
B1 = 130000, B2 = 2827500 (P-1 stage 2)
B1 = 130000 (P-1 stage 1)
B1 = 35000, B2 = 288750 (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
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270
280
Last modified: 2023-04-26T21:34:10+00:00