is 2 2756797 - 1
has 829879 decimal digits
takes 0.213 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LBA2C9F9E847EF948double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26821.621167.6471%2700000840000000.79847.6786%22.419570.1313%2.4842%
PrimeNet2590.027962.7119%120002200000.00262.8538%0.030563.7760%1.0641%
GPU722630.578965.0794%150002400000.00311.7447%0.582065.6886%0.6092%
Difference+5+21.0421+2.5677%+2685000+83760000+0.7954+5.9339%+21.8375+4.4427%+4.4427%

Known prime factors (1 factor, 76.0 bits, 0.00275652% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2756797751156999120329775445592375.99213623727084735107
3 × 17 × 83833 × 3186476729
2020-08-038383331864767294,414.019.45236.314

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-11-16T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.242%
2003-11-28T00:00:00Team Prime Ribv4_computers15000225000---0.003--0.799%
2010-12-21T11:04:00Jocelyn LaroucheManual testing2000020000---0.002--0.270%
2011-01-02T14:09:00Jocelyn LaroucheManual testing3000030000---0.003--0.373%
2011-01-23T12:18:00Jocelyn LaroucheManual testing5000050000---0.006--0.539%
2011-05-07T14:06:00James HeinrichWHS1900004655000---0.049--3.336%
2016-12-27T08:05:15mikrMSI27000008400000012---0.798--7.679%
2017-01-10T10:25:14Jocelyn Larouchelow 4M228000228000---0.026--1.311%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2016-02-23T16:29:20Mark RoseManual testing21260--0.056--
2009-02-13T21:37:00Sturle Sundeghibu.ifi260261--0.056--
2012-03-27T07:26:00markroldgamer261262--0.111--
2013-01-14T12:31:00dbaughManual testing262263--0.356--
2015-04-21T09:20:00VictordeHollanderManual testing263264--0.712--
2015-04-21T09:20:00VictordeHollanderManual testing264265--1.355--
2016-02-05T15:45:59ramgeisManual testing265266--2.711--
2017-10-09T09:26:12Gordon SpenceManual testing266267--5.421--
2019-02-20T01:17:43chuenkitManual testing267268--10.84--


ECM factoring results:

Old Calculation Method

Total ECM effort:3.222 GHz-days
Estimated T-Level:1.550
DigitsB1CurvesCompleteFacMiss
201100031 / 1000.31073.230%
255000031 / 2800.11189.502%

New Calculation Method

Total ECM effort:3.222 GHz-days
Estimated T-Level:1.550
DigitsB1CompleteFacMiss
20110001.00036.788%
25500000.09091.358%
302500000.00699.445%


ECM Summary

B1B2factorcurvesGHz-days
500005000000303.118
50000500000010.104


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-07-04T00:00:00ANONYMOUSv4_computersBA2C9F9E847EF9480.213
2018-08-15T22:51:21kkmrkkblmbrbkoldBA2C9F9E847EF9480.213


PRP results:
dateuseridcompidcofactorsres64PRP
2020-08-07T01:36:46fre_gamesgpu
75115699912032977544559
21F7B366D88F6EADno
2020-08-07T19:20:19marssystemsSYSTEM01
75115699912032977544559
21F7B366D88F6EADno


P-1 factor-bounds graph:
B1 = 2700000, B2 = 84000000 (P-1 stage 2)
B1 = 2700000 (P-1 stage 1)
B1 = 190000, B2 = 4655000 (P-1 stage 2)
B1 = 228000 (P-1 stage 1)
B1 = 190000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 225000 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
103
104
105
106
107
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
250
260
270
280
290
2100
Last modified: 2020-08-07T19:20:19+00:00