is 2 6993221 - 1
has 2105170 decimal digits
takes 1.525 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L7EE39E1787A560BAdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual272136.751568.0556%20000002586265505.05316.9845%141.804670.2867%
Target2674.249065.6716%450009000000.02902.2402%4.277966.4407%
Difference+5+132.5026+2.3839%+1955000+257726550+5.0242+4.7443%+137.5267+3.8461%

Known prime factors:
No known factors for M6993221

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-09-22Gregory Czajkowskiv4_computers3000030000---0.009--0.235%
2011-05-22Carsten Kossendeymother44500013572500---0.367--3.529%
2021-11-08Seth_TrManual testing30000007500000012---2.189--5.988%
2021-12-06Seth_TrManual testing2000000258626550---5.053--6.985%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-12-13ANONYMOUSv4_computers21262--0.088--
2016-02-23Mark RoseManual testing262263--0.140--
2014-01-17lycornManual testing263264--0.281--
2014-01-18lycornManual testing264265--0.534--
2015-07-03VictordeHollanderManual testing265266--1.069--
2016-04-28Gordon SpenceManual testing266267--2.137--
2018-02-26-Anonymous-Manual testing267268--4.274--
2020-04-03TJAOIManual testing268269--8.549--
2020-07-26takahashiManual testing269270--17.10--
2020-09-16takahashiManual testing270271--34.19--
2021-09-28SRBaseManual testing271272--68.39--


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_computers30A59112DCB18A__1.525
1999-07-26ANONYMOUSv4_computers7EE39E1787A560BA1.525
2001-11-03Gregory Czajkowskiv4_computers7EE39E1787A560BA1.525


PRP results:
No PRP results for M6993221


P-1 factor-bounds graph:
B1 = 2000000, B2 = 258626550 (P-1 stage 2)
B1 = 3000000, B2 = 75000000 (P-1 stage 2)
B1 = 3000000 (P-1 stage 1)
B1 = 2000000 (P-1 stage 1)
B1 = 445000, B2 = 13572500 (P-1 stage 2)
B1 = 445000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
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105
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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: 67.7
ECM T-Level=1.15 ~= -13-bit
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Last modified: 2023-03-23T17:39:31+00:00