1368
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 3900
- Proper Divisor Sum (Aliquot Sum)
- 2532
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 432
- Möbius Function
- 0
- Radical
- 114
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 3
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 127
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Number of 2n-step self-avoiding walks on diamond lattice ending at point with x = 2.at n=3A001397
- Number of ways of folding a 3 X n strip of stamps.at n=3A001416
- Number of ways of folding an n X n sheet of stamps.at n=2A001418
- Total diameter of unlabeled trees with n nodes.at n=10A001851
- Cluster series for site percolation problem on honeycomb matching lattice (honeycomb structure with 1st, 2nd and 3rd neighbors connected).at n=4A003200
- Self numbers divisible by sum of their digits (or, self numbers which are also Harshad numbers).at n=34A003219
- Theta series of D_4 lattice; Fourier coefficients of Eisenstein series E_{gamma,2}.at n=49A004011
- a(n) = floor(n*phi^9), where phi is the golden ratio, A001622.at n=18A004924
- a(n) = round(n*phi^9), where phi is the golden ratio, A001622.at n=18A004944
- Number of n-bead bracelets (turnover necklaces) with 12 red beads.at n=7A005516
- a(n) = n*(n+2) = (n+1)^2 - 1.at n=36A005563
- Number of loopless tree-rooted planar maps with 4 vertices and n faces.at n=3A006429
- Low temperature series for spin-1/2 Ising antiferromagnetic susceptibility for 3-dimensional b.c.c. lattice.at n=11A007218
- Jordan function J_2(n) (a generalization of phi(n)).at n=36A007434
- Coordination sequence T2 for Zeolite Code AFR.at n=28A008020
- Coordination sequence T3 for Zeolite Code PAU.at n=27A008221
- Molien series of 4-dimensional representation of cyclic group of order 4 over GF(2) (not Cohen-Macaulay).at n=30A008610
- High temperature expansion of -u/J in odd powers of v = tanh(J/kT), where u is energy per site of the spin-1/2 Ising model on cubic lattice with nearest-neighbor interaction J at temperature T.at n=3A010571
- a(n) = floor( n*(n-1)*(n-2)/5 ).at n=20A011887
- Numbers k such that the periodic part of the continued fraction for sqrt(k) contains a single 1.at n=42A013648