is 2 6907853 - 1
has 2079471 decimal digits
takes 1.506 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L163CED669656D3FEdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272138.441568.0556%1000000300000000.81574.5582%139.257369.5117%
Target2674.301565.6716%450009000000.02902.2356%4.330466.4391%
Difference+5+134.1400+2.3839%+955000+29100000+0.7868+2.3226%+134.9268+3.0726%

Known prime factors:
No known factors for M6907853

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2009-06-09Roman MaznichenkoWorkShop850001572500---0.052--1.581%
2019-05-08takahashivaio30000050000006---0.176--2.681%
2021-05-14takahashivaio10000003000000012---0.816--4.558%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-06-29ANONYMOUSv4_computers21262--0.089--
1998-08-09ANONYMOUSv4_computers21262--0.089--
1998-08-24ANONYMOUSv4_computers21262--0.089--
1998-08-30ANONYMOUSv4_computers21262--0.089--
1998-10-18ANONYMOUSv4_computers21262--0.089--
1998-10-25ANONYMOUSv4_computers21262--0.089--
1998-11-28ANONYMOUSv4_computers21262--0.089--
2005-07-01ANONYMOUSv4_computers21263--0.231--
2014-02-09NesowaManual testing263264--0.284--
2014-02-18lycornManual testing264265--0.541--
2015-06-21VictordeHollanderManual testing265266--1.082--
2016-04-01Gordon SpenceManual testing266267--2.164--
2018-05-23ramgeisManual testing267268--4.327--
2019-12-31mnd9Manual testing268269--8.654--
2020-12-21takahashiManual testing269270--17.31--
2021-08-10SRBaseManual testing270271--34.62--
2021-09-25SRBaseManual testing271272--69.23--


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)
1999-03-26netconxv4_computers163CED669656D3FE1.506
2001-08-31ANONYMOUSv4_computers163CED669656D3FE1.506


PRP results:
No PRP results for M6907853


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 = 1572500 (P-1 stage 2)
B1 = 85000 (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
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