13608
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 48
- Divisor Sum
- 43680
- Proper Divisor Sum (Aliquot Sum)
- 30072
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3888
- Möbius Function
- 0
- Radical
- 42
- Omega Function (Ω)
- 9
- 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
- 63
- 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
- Triangle of coefficients in expansion of (1+3*x)^n.at n=41A013610
- Alkane (or paraffin) numbers l(9,n).at n=13A018210
- Cube of lower triangular normalized binomial matrix.at n=39A027465
- Theta series of tensor cube of A_2 lattice (dimension 8, det 3^12).at n=39A033688
- Expansion of 1/(1 - 3*x)^4; 4-fold convolution of A000244 (powers of 3).at n=5A036216
- Number of ternary Lyndon words of length n with trace 0 and subtrace 1 over GF(3).at n=12A053560
- Number of ternary Lyndon words of length n with trace 0 and subtrace 2 over GF(3).at n=12A053561
- Number of ternary Lyndon words of length n with trace 1 and subtrace 1 over GF(3). Same as the number of ternary Lyndon words of length n with trace 2 and subtrace 1 over GF(3).at n=12A053563
- Number of ternary Lyndon words of length n with trace 1 and subtrace 2 over GF(3). Same as the number of ternary Lyndon words of length n with trace 2 and subtrace 2 over GF(3).at n=12A053564
- Scaled Chebyshev U-polynomials evaluated at i*sqrt(6)/2. Generalized Fibonacci sequence.at n=5A057089
- Triangle of idempotent numbers binomial(n,k)*k^(n-k), version 1.at n=39A059297
- Triangle of idempotent numbers binomial(n,k)*k^(n-k), version 2.at n=30A059298
- Triangle of idempotent numbers (version 3), T(n, k) = binomial(n, k) * (n - k)^k.at n=41A059299
- Triangle of idempotent numbers binomial(n,k)*k^(n-k), version 4.at n=33A059300
- Look at all numbers formed by multiplying the parts in a partition of n; a(n) = maximal such number which is divisible by n.at n=27A069188
- Triangle of generalized Stirling numbers S_{3,3}(n,k) read by rows (n>=1, 3<=k<=3n).at n=13A078741
- Numbers divisible by twice the sum of the products of each of their digits, excluding even multiples of 10.at n=35A085446
- Numbers n such that sopfr(n)/spf(n) is a semiprime and sopfr(n)/lpf(n) is a semiprime, where sopfr(n) = A001414(n) is sum of primes dividing n (with repetition), spf(n) and lpf(n) are smallest and largest primes dividing n, respectively. Also, spf(n)!=lpf(n).at n=23A085718
- a(n) = 18n^3 + 6n^2.at n=9A087887
- Riordan array (1, 3+x).at n=74A099097