is 2 5164853 - 1
has 1554776 decimal digits
takes 0.816 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L7587DA64C1B68EFEdouble-checked
PRP8DF28B3FC12359D2PRP-tested

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual27192.563867.6056%400000010285831710129.186112.0437%221.749871.5071%3.9015%
PrimeNet2620.119062.9032%220004500000.01042.9227%0.129363.9875%1.0842%
GPU722662.859465.1515%300005500000.01341.9401%2.872865.8276%0.6761%
Difference+5+89.7044+2.4541%+3970000+10285281710+129.1727+10.1036%+218.8771+5.6795%+3.2254%

Known prime factors (1 factor, 126.5 bits, 0.00245016% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
516485312428963886245859505876356611877051256139126.54712032253276371911752257379456760
23 × 5 × 7 × 172 × 641 × 5987 × 14401 × 2560361 × 1050823919
2022-07-17256036110508239193.578e+1013.66424.485

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2009-08-25T14:20:00Carsten Kossendeyleela25000325000---0.009--0.772%
2009-09-30T03:46:00harleeP4_260055000935000---0.024--1.337%
2016-05-26T01:40:45Ismo Laitela16927175078150612---1.000--5.610%
2022-07-17T01:22:32Sid & AndyMagic_8_Ball40000001028583171039126.547129.21.631258.412.044%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2016-02-23T16:39:10Mark RoseManual testing21262--0.119--
2009-06-24T14:54:00GrunwalderGIMPManual testing262263--0.190--
2014-12-17T21:26:00VictordeHollanderManual testing263264--0.380--
2014-12-17T21:26:00VictordeHollanderManual testing264265--0.723--
2015-08-09T01:07:00snme2pm1Manual testing265266--1.447--
2016-06-03T16:02:22Gordon SpenceManual testing266267--2.894--
2018-06-20T10:29:35ramgeisManual testing267268--5.787--
2020-11-16T18:25:14TJAOIManual testing268269--11.57--
2022-01-16T19:42:12Gordon SpenceManual testing269270--23.15--
2022-01-25T19:40:15mikrManual testing270271--46.30--


ECM factoring results:
Total ECM effort:2.161 GHz-days
Estimated T-Level:1.731
DigitsB1CompleteFacMiss
20110000.34670.740%
25500000.03296.848%
302500000.00299.798%


ECM Summary

B1B2factorcurvesGHz-days
50000500000092.161


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2000-04-27T00:00:00GlennMaitzv4_computers7587DA64C1B68EFE0.816


PRP results:
dateuseridcompidcofactorsres64PRP
2022-07-23T19:42:53Ryan Propperboulder
124289638862458595058763566118770512561
8DF28B3FC12359D2no


P-1 factor-bounds graph:
B1 = 4000000, B2 = 10285831710 (P-1 stage 2)
B1 = 1692717, B2 = 50781506 (P-1 stage 2)
B1 = 4000000 (P-1 stage 1)
B1 = 1692717 (P-1 stage 1)
B1 = 55000, B2 = 935000 (P-1 stage 2)
B1 = 55000 (P-1 stage 1)
B1 = 25000, B2 = 325000 (P-1 stage 2)
B1 = 25000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
109
1010
1011
TF factor-bounds graph:
271
270
269
268
267
266
265
264
263
262
250
260
270
280
290
2100
2110
2120
2130
Last modified: 2022-07-23T19:42:53+00:00