is 2 2588753 - 1
has 779293 decimal digits
takes 0.180 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LD44424DAE0FD7423double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26711.478167.1642%32000001120000000.91808.7565%12.396170.0395%2.8753%
PrimeNet2590.029762.7119%110002000000.00212.6927%0.031863.7159%1.0041%
GPU722630.616565.0794%120002000000.00221.5290%0.618865.6133%0.5339%
Difference+4+10.8616+2.0848%+3188000+111800000+0.9158+7.2275%+11.7773+4.4261%+4.4261%

Known prime factors (1 factor, 104.3 bits, 0.00402984% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
25887532536539648787947154113746082604932104.3234899153470392785936151008
25 × 32 × 7 × 211 × 63247 × 3146371 × 57875959
2016-08-123146371578759596.176e+100.61630.6440

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-31T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.294%
2003-11-08T00:00:00Team Prime Ribv4_computers15000206250---0.003--0.897%
2010-11-15T22:51:00Jocelyn LaroucheManual testing2000020000---0.002--0.316%
2011-01-13T23:58:00Jocelyn LaroucheManual testing5000050000---0.005--0.622%
2011-10-14T12:39:00markrtiny1750004112500---0.039--3.544%
2016-08-12T05:52:16mikrMSI32000001120000001232104.3230.9180.3591.8368.757%
2019-07-04T12:41:52alpertronManual testing20000006000000012---0.519--7.675%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-26T00:00:00ANONYMOUSv4_computers21259--0.030--
1999-04-13T00:00:00ANONYMOUSv4_computers21259--0.030--
2016-02-23T16:29:17Mark RoseManual testing259260--0.030--
2009-01-31T00:40:00Sturle Sundebach.ifi260261--0.059--
2012-06-22T17:42:00Sebastian HornbostelManual testing261262--0.119--
2013-01-14T11:55:00dbaughManual testing262263--0.379--
2015-02-27T20:35:00VictordeHollanderManual testing263264--0.758--
2015-02-27T20:35:00VictordeHollanderManual testing264265--1.443--
2015-11-06T09:16:15ramgeisManual testing265266--2.887--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.941 GHz-days
Estimated T-Level:1.050
DigitsB1CurvesCompleteFacMiss
201100021 / 1000.21080.973%
255000021 / 2800.07592.762%

New Calculation Method

Total ECM effort:1.941 GHz-days
Estimated T-Level:1.050
DigitsB1CompleteFacMiss
20110000.67750.793%
25500000.06194.061%
302500000.00499.624%


ECM Summary

B1B2factorcurvesGHz-days
500005000000211.941


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-26T00:00:00ANONYMOUSv4_computersD44424DAE0FD74230.180
1999-04-13T00:00:00ANONYMOUSv4_computersD44424DAE0FD74230.180


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-15T12:26:59Oliver KruseGTX-1
25365396487879471541137460826049
811A8450A24CF7__no
2017-12-02T02:59:43storm5510HP-Z220-CMT
25365396487879471541137460826049
811A8450A24CF7__no


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 2000000, B2 = 60000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 2000000 (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 = 206250 (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
TF factor-bounds graph:
267
266
265
264
263
262
261
260
259
250
260
270
280
290
2100
2110
Last modified: 2019-07-04T12:41:52+00:00