is 2 2176547 - 1
has 655206 decimal digits
takes 0.143 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L0849F817E2D4AD4Cdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26827.385167.6471%50000002000000001.48968.9481%28.874670.5420%2.8950%
PrimeNet2580.017662.0690%100001800000.00182.8574%0.019563.1528%1.0839%
GPU722620.282364.5161%110001600000.00181.5682%0.284165.0726%0.5565%
Difference+6+27.1028+3.1309%+4989000+199840000+1.4877+7.3799%+28.5905+5.4694%+5.4694%

Known prime factors (1 factor, 90.9 bits, 0.00417420% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
217654722366833536801917417403405212890.853513814623272594559580
22 × 5 × 7 × 97 × 163 × 181 × 51131 × 25081657
2019-11-225113125081657122,184,4130.13490.2433

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-03-07T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.226%
2010-11-05T01:17:00Jocelyn LaroucheManual testing1500015000---0.001--0.198%
2010-11-08T01:30:00Jocelyn LaroucheManual testing3000030000---0.003--0.354%
2011-01-15T01:41:00markrtiny900001620000---0.017--2.204%
2014-06-13T02:40:00Jocelyn LaroucheManual testing119489119489---0.011--0.890%
2014-10-05T22:22:00Jocelyn LaroucheManual testing148978148978---0.014--1.007%
2015-12-22T14:03:57HBendtzManual testing7000002100000012---0.172--5.205%
2019-11-22T18:12:03mikrMSI5000000200000000122890.8531.4900.2862.9798.948%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-02-07T00:00:00ANONYMOUSv4_computers21258--0.018--
2016-02-23T16:29:07Mark RoseManual testing258260--0.053--
2009-01-05T05:04:00Sturle Sundeantonov.ifi260261--0.071--
2009-01-07T22:32:00Sturle Sundegonsha.ifi261262--0.141--
2013-09-09T08:39:00ramgeisManual testing262263--0.451--
2015-03-25T10:09:00VictordeHollanderManual testing263264--0.902--
2015-03-25T10:09:00VictordeHollanderManual testing264265--1.717--
2016-01-02T13:50:57ramgeisManual testing265266--3.433--
2016-11-17T17:00:13Gordon SpenceManual testing266267--6.867--
2019-04-29T13:20:33TJAOIManual testing267268--13.73--


ECM factoring results:

Old Calculation Method

Total ECM effort:3.334 GHz-days
Estimated T-Level:1.950
DigitsB1CurvesCompleteFacMiss
201100039 / 1000.39067.573%
255000039 / 2800.13986.976%

New Calculation Method

Total ECM effort:3.334 GHz-days
Estimated T-Level:1.950
DigitsB1CompleteFacMiss
20110001.25828.420%
25500000.11489.252%
302500000.00799.302%


ECM Summary

B1B2factorcurvesGHz-days
500005000000393.334


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-02-14T00:00:00ANONYMOUSv4_computers0849F817E2D4AD4C0.143
2018-04-12T23:33:17kkmrkkblmbrbkold0849F817E2D4AD4C0.143


PRP results:
dateuseridcompidcofactorsres64PRP
2019-11-23T05:31:04mnd9eileen
2236683353680191741740340521
103DCB62BB9D93B3no
2019-11-30T02:48:24NesowaLaptop
2236683353680191741740340521
103DCB62BB9D93B3no


P-1 factor-bounds graph:
B1 = 5000000, B2 = 200000000 (P-1 stage 2)
B1 = 5000000 (P-1 stage 1)
B1 = 700000, B2 = 21000000 (P-1 stage 2)
B1 = 700000 (P-1 stage 1)
B1 = 90000, B2 = 1620000 (P-1 stage 2)
B1 = 148978 (P-1 stage 1)
B1 = 119489 (P-1 stage 1)
B1 = 90000 (P-1 stage 1)
B1 = 30000 (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:
268
267
266
265
264
263
262
261
260
258
250
260
270
280
290
2100
Last modified: 2019-11-30T02:48:24+00:00