is 2 1216961 - 1
has 366342 decimal digits
takes 0.037 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LEB470D5F81B003CCdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26724.416568.6567%1205000349450000.13536.1883%24.551870.5963%1.9396%
PrimeNet2560.007962.5000%5500800000.00042.3420%0.008363.3782%0.8782%
GPU722600.126265.0000%5000300000.00030.8284%0.126565.2900%0.2900%
Difference+7+24.2903+3.6567%+1200000+34915000+0.1350+5.3599%+24.4253+5.3064%+5.3064%

Known prime factors (1 factor, 64.2 bits, 0.00527304% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1216961207655145650232759592064.1718531709136539
3 × 311 × 9144382783
2013-12-1831191443827833.827922.15441.377

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-09-07T00:00:00Jocelyn Larouchev4_computers10001000---4.44667e-5--0.005%
2002-11-16T00:00:00Jocelyn Larouchev4_computers1000010000---0.000--0.140%
2003-09-21T00:00:00Team Prime Ribv4_computers100001000000---0.003--0.995%
2013-10-07T20:36:00David CampeauManual testing120500034945000---0.135--6.188%
2016-03-17T19:02:22alpertronManual testing3000001000000012---0.037--4.169%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2001-11-10T00:00:00ANONYMOUSv4_computers21257--0.016--
2003-05-19T00:00:00ANONYMOUSv4_computers21258--0.032--
2022-03-07T17:31:39LordJuliusManual testing258260--0.095--
2009-02-17T05:43:00Sturle Sundegiacco.ifi260261--0.126--
2022-04-13T02:44:43LordJuliusManual testing21261--0.252--
2011-05-09T14:46:00XyzzyManual testing261262--0.252--
2022-04-13T02:44:43LordJuliusManual testing261262--0.252--
2012-10-13T12:00:00dbaughManual testing262263--0.807--
2022-04-13T02:44:43LordJuliusManual testing262263--0.807--
2022-04-13T02:44:43LordJuliusManual testing263264--1.613--


ECM factoring results:

Old Calculation Method

Total ECM effort:19.618 GHz-days
Estimated T-Level:25.344
DigitsB1CurvesCompleteFacMiss
2011000322 / 1003.2203.931%
2550000322 / 2801.15031.599%
3025000044 / 6400.06993.351%

New Calculation Method

Total ECM effort:19.618 GHz-days
Estimated T-Level:25.344
DigitsB1CompleteFacMiss
201100015.0920.000%
25500001.65619.090%
302500000.13787.221%
3510000000.00999.079%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
50000500000027810.27
25000035000000449.346


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2002-08-10T00:00:00ANONYMOUSv4_computersEB470D5F81B003CC0.037


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-29T15:02:36Oliver KruseGTX-1
20765514565023275959
93A7D6F998A53B__no
2017-10-18T04:01:29Oliver KruseThreadripper
20765514565023275959
93A7D6F998A53B__no
2018-01-03T02:32:09ATHec2-8x
20765514565023275959
93A7D6F998A53B__no


P-1 factor-bounds graph:
B1 = 1205000, B2 = 34945000 (P-1 stage 2)
B1 = 1205000 (P-1 stage 1)
B1 = 300000, B2 = 10000000 (P-1 stage 2)
B1 = 300000 (P-1 stage 1)
B1 = 10000, B2 = 1000000 (P-1 stage 2)
B1 = 10000 (P-1 stage 1)
B1 = 1000 (P-1 stage 1)
101
102
103
104
105
106
107
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
267
264
263
262
261
260
258
257
250
260
270
280
290
2100
Last modified: 2022-04-13T02:44:43+00:00