is 2 8121689 - 1
has 2444873 decimal digits
takes 2.121 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L6D06E2A1A087F092double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual273235.523068.4932%150000080916957017.22837.3536%252.751370.8100%2.3169%
PrimeNet2630.196563.4921%360009000000.03153.6144%0.228064.8116%1.3195%
GPU722673.658665.6716%5500012000000.04442.5730%3.703066.5549%0.8833%
Difference+6+231.8644+2.8215%+1445000+807969570+17.1839+4.7806%+249.0483+4.2551%+1.4336%

Known prime factors:
No known factors for M8121689

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-08-03T00:00:00ANONYMOUSv4_computers45000573750---0.028--0.905%
2012-09-22T14:52:00James HeinrichManual testing2150005375000---0.188--2.358%
2022-03-21T19:23:00FlaukrotistColab_HLM21500000809169570---17.23--7.354%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-08-24T00:00:00ANONYMOUSv4_computers21261--0.038--
1998-08-30T00:00:00ANONYMOUSv4_computers21262--0.076--
1999-01-02T00:00:00ANONYMOUSv4_computers21263--0.197--
2013-09-15T18:13:00AxelssonManual testing263264--0.242--
2013-12-26T16:28:00David CampeauManual testing264265--0.460--
2015-05-25T01:07:00snme2pm1Manual testing265266--0.920--
2015-11-30T20:43:33snme2pm1Manual testing266267--1.840--
2018-07-03T10:21:56chuenkitManual testing267268--3.680--
2019-12-02T02:26:58mnd9Manual testing268269--7.361--
2021-08-20T16:56:54SRBaseManual testing269270--14.72--
2021-08-31T20:32:04SRBaseManual testing270271--29.44--
2021-10-13T15:13:37SRBaseManual testing271272--58.89--
2022-09-04T16:27:07FlaukrotistManual testing272273--117.8--


ECM factoring results:
Total ECM effort:2.382 GHz-days
Estimated T-Level:1.154
DigitsB1CompleteFacMiss
20110000.23179.392%
25500000.02197.887%
302500000.00199.865%


ECM Summary

B1B2factorcurvesGHz-days
50000500000062.382


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-10-07T00:00:00ANONYMOUSv4_computers6D06E2A1A087F0922.121
2002-08-17T00:00:00ANONYMOUSv4_computers6D06E2A1A087F0922.121


PRP results:
No PRP results for M8121689


P-1 factor-bounds graph:
B1 = 1500000, B2 = 809169570 (P-1 stage 2)
B1 = 1500000 (P-1 stage 1)
B1 = 215000, B2 = 5375000 (P-1 stage 2)
B1 = 215000 (P-1 stage 1)
B1 = 45000, B2 = 573750 (P-1 stage 2)
B1 = 45000 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-09-04T16:27:07+00:00