is 2 2176171 - 1
has 655093 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-L9903D3C651CFCD60double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26713.654267.1642%500000150000000.12305.1753%13.777268.8635%1.6993%
PrimeNet2580.017662.0690%100001800000.00182.8573%0.019563.1528%1.0838%
GPU722620.282364.5161%110001600000.00181.5682%0.284165.0726%0.5565%
Difference+5+13.3719+2.6481%+489000+14840000+0.1212+3.6071%+13.4931+3.7909%+3.7909%

Known prime factors (2 factors, 135.0 bits, 0.00620242% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
217617116750531844306592491960.539384862491144
23 × 32 × 5345312377
2009-01-05953453123770.106727.76551.857
2176171255616855456906071873592374.4365873087534410349
11 × 67 × 7968911172877
2009-01-046779689111728772,088.841,39377,310

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
21761714281718277272420534836024957871802923339141134.975
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-03-07T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.280%
2016-03-15T11:16:43alpertronManual testing5000001500000012---0.123--5.175%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2009-01-05T00:22:00Sturle Sundeantonov.ifi??60.539190.0360.2910.073
1999-01-29T00:00:00ANONYMOUSv4_computers21258--0.018--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.577 GHz-days
Estimated T-Level:0.850
DigitsB1CurvesCompleteFacMiss
201100017 / 1000.17084.294%
255000017 / 2800.06194.099%

New Calculation Method

Total ECM effort:1.577 GHz-days
Estimated T-Level:0.850
DigitsB1CompleteFacMiss
20110000.68750.306%
25500000.06393.860%
302500000.00499.599%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
50000500000030.256
50000545000070.621
50000706136870.700


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-01T00:00:00ANONYMOUSv4_computers9903D3C651CFCD600.143


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-10T00:11:15kkmrkkblmbrbkManual testing
1675053184430659249
25561685545690607187359
83E1F160ADA642__no
2017-10-23T05:45:39Oliver KruseGTX-3
1675053184430659249
25561685545690607187359
83E1F160ADA642__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
100
101
102
103
104
105
106
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
1013
TF factor-bounds graph:
267
258
2
250
260
270
280
290
2100
Last modified: 2022-06-15T21:03:17+00:00