is 2 1719857 - 1
has 517729 decimal digits
takes 0.081 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LAEC1C83AF7FF21C2double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26717.277068.6567%500000150000000.08805.0308%17.365070.2335%1.5768%
PrimeNet2570.011263.1579%80001400000.00102.7933%0.012264.1870%1.0291%
GPU722610.178665.5738%70001100000.00091.3436%0.179566.0363%0.4626%
Difference+6+17.0984+3.0829%+493000+14890000+0.0872+3.6871%+17.1855+4.1972%+4.1972%

Known prime factors (2 factors, 177.3 bits, 0.01030843% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
17198571256647209499000074241003192786.70036533479513093241887
13 × 47 × 2609339 × 22914971503
2014-10-2526093392291497150313,622,75485.365159.12
171985718641676295215590281139973832890.591541954252452837366163
7 × 16927 × 58031 × 157561 × 500237
2015-06-06157561500237209,633,0190.01200.0219

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
171985723426010496766329435371402302139407211015793949546
5177
54177.290
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2011-02-07T12:33:00Carsten Kossendeyleela900001507500---0.011--2.356%
2014-04-04T00:13:00Jocelyn LaroucheManual testing100000100000---0.007--0.885%
2014-05-03T14:50:00Jocelyn LaroucheManual testing150000150000---0.010--1.110%
2014-10-06T21:12:00Jocelyn LaroucheManual testing187319187319---0.013--1.248%
2015-06-06T12:14:00alpertronManual testing50000015000000122890.5910.0880.1620.1765.031%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2003-02-02T00:00:00ANONYMOUSv4_computers21258--0.022--
2010-04-24T12:42:00Architects Cubeda3_bu2260261--0.089--
2010-10-27T20:37:00GrunwalderGIMPManual testing21263--0.928--


ECM factoring results:

Old Calculation Method

Total ECM effort:15.295 GHz-days
Estimated T-Level:24.589
DigitsB1CurvesCompleteFacMiss
2011000257 / 1002.5707.555%
2550000257 / 2800.91839.872%

New Calculation Method

Total ECM effort:15.295 GHz-days
Estimated T-Level:24.589
DigitsB1CompleteFacMiss
20110008.2900.025%
25500000.74947.271%
302500000.04695.491%
3510000000.00299.789%


ECM Summary

B1B2factorcurvesGHz-days
50000500000025515.18
50000500000020.119


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-02T00:00:00Phantomasv4_computersAEC1C83AF7FF21C20.081


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-30T15:24:36alpertronManual testing
125664720949900007424100319
1864167629521559028113997383
7CF7F1272E39C3__no
2017-10-19T02:23:29Oliver KruseThreadripper
125664720949900007424100319
1864167629521559028113997383
7CF7F1272E39C3__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
B1 = 187319 (P-1 stage 1)
B1 = 90000, B2 = 1507500 (P-1 stage 2)
B1 = 150000 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 90000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
109
1010
1011
TF factor-bounds graph:
267
263
261
258
250
260
270
280
290
2100
Last modified: 2020-05-04T10:43:43+00:00