is 2 2571827 - 1
has 774198 decimal digits
takes 0.178 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
1 primality tests remaining
ResidueStatus
L-L0093CBF2646C99E8double-checked
PRPB2C2413CFC6C56__verified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26946.421068.1159%32000001120000000.91807.4498%47.339070.4913%2.3753%
PrimeNet2590.029962.7119%110002000000.00212.6895%0.032063.7147%1.0029%
GPU722630.620665.0794%120001900000.00221.5043%0.622865.6047%0.5253%
Difference+6+45.8004+3.0366%+3188000+111810000+0.9158+5.9455%+46.7163+4.8866%+4.8866%

Known prime factors (1 factor, 80.5 bits, 0.00313105% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
257182717399068751149628429380092580.525338262813773042052
22 × 3 × 4729 × 5960788288099
2021-12-0647295960788288099115,24332,66261,004

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-31T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.191%
2003-11-08T00:00:00Team Prime Ribv4_computers15000202500---0.003--0.650%
2010-12-21T01:10:00Jocelyn LaroucheManual testing2000020000---0.002--0.222%
2011-01-10T23:58:00Jocelyn LaroucheManual testing5000050000---0.005--0.455%
2011-04-17T07:39:00James HeinrichWHS1750004112500---0.039--2.840%
2016-06-15T16:15:43mikrMSI320000011200000012---0.918--7.450%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-11-07T00:00:00ANONYMOUSv4_computers21258--0.015--
1999-10-29T00:00:00ANONYMOUSv4_computers21258--0.015--
1999-03-26T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:16Mark RoseManual testing259260--0.030--
2009-01-30T09:32:00Sturle Sundescarpia.ifi260261--0.060--
2012-06-19T05:42:00Sebastian HornbostelManual testing261262--0.119--
2013-01-14T11:55:00dbaughManual testing262263--0.382--
2015-02-23T17:24:00VictordeHollanderManual testing263264--0.763--
2015-02-23T17:24:00VictordeHollanderManual testing264265--1.453--
2015-11-08T21:03:04ramgeisManual testing265266--2.906--
2017-08-20T12:59:32Gordon SpenceManual testing266267--5.811--
2019-09-05T13:49:26YxinityManual testing267268--11.62--
2021-06-10T09:21:17TJAOIManual testing268269--23.24--


ECM factoring results:

Old Calculation Method

Total ECM effort:12.660 GHz-days
Estimated T-Level:22.429
DigitsB1CurvesCompleteFacMiss
2011000136 / 1001.36025.491%
2550000136 / 2800.48661.472%

New Calculation Method

Total ECM effort:12.660 GHz-days
Estimated T-Level:22.429
DigitsB1CompleteFacMiss
20110004.4101.215%
25500000.39867.142%
302500000.02597.576%
3510000000.00199.888%


ECM Summary

B1B2factorcurvesGHz-days
50000500000012011.08
50000500000020.185
50000515000070.655
50000675000070.742


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-11-07T00:00:00ANONYMOUSv4_computers0093CBF2646C99E80.178
1999-04-13T00:00:00ANONYMOUSv4_computers0093CBF2646C99E80.178
1999-10-29T00:00:00ANONYMOUSv4_computers0093CBF2646C99E80.178
2018-06-16T23:25:14kkmrkkblmbrbkold0093CBF2646C99E80.178


PRP results:
dateuseridcompidcofactorsres64PRP
2021-12-08T23:19:15MarkSdesktop-i7
1739906875114962842938009
B2C2413CFC6C56__no


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 175000, B2 = 4112500 (P-1 stage 2)
B1 = 175000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 15000, B2 = 202500 (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
1011
1012
1013
TF factor-bounds graph:
269
268
267
266
265
264
263
262
261
260
259
258
250
260
270
280
290
2100
Last modified: 2021-12-08T23:19:15+00:00