13504
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 14
- Divisor Sum
- 26924
- Proper Divisor Sum (Aliquot Sum)
- 13420
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6720
- Möbius Function
- 0
- Radical
- 422
- Omega Function (Ω)
- 7
- Little Omega Function (ω)
- 2
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
- no
- Narcissistic Number
- no
- Collatz Steps
- 45
- 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
- [ n(n-1)(n-2)(n-3)/13 ].at n=22A011923
- Numbers k such that phi(k) + 11 | sigma(k).at n=10A015804
- Numbers k such that the continued fraction for sqrt(k) has period 92.at n=32A020431
- Number of 3's in n-th term of A022470.at n=39A022474
- Numbers k such that k^2 is palindromic in base 15.at n=45A030073
- Composite numbers k such that the digits of the prime factors of k are either 1 or 2.at n=45A036302
- Numbers n such that n^3 is palindromic in base 15.at n=12A046251
- Number of connected 4-regular simple graphs on n vertices with girth at least 6.at n=37A058348
- Triangle T(n, k) is coefficient of z^n*w^k in 1/(1 - 2*z - 2*w - 2*z*w) read by rows in order 00, 10, 01, 20, 11, 02, ...at n=42A059473
- Triangle T(n, k) is coefficient of z^n*w^k in 1/(1 - 2*z - 2*w - 2*z*w) read by rows in order 00, 10, 01, 20, 11, 02, ...at n=38A059473
- Expansion of g.f. x*(1+x)^5/(1-x)^7.at n=8A069039
- Sum of n-th row of triangle in A082196.at n=28A082199
- Number of subsets of {1, ..., n} that are not double-free.at n=14A088808
- a(n) = 4*n^3 + 4.at n=15A100214
- Sequence of Mahler coefficients of the Gray code function.at n=14A109629
- Triangle read by rows: T(n,k) is the number of deco polyominoes of height n with k cells in the second row (0<=k<=n-1; a deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column).at n=38A134436
- a(n) = p(n)*p(n+2) - 3*p(n+1), where p(n) is the n-th prime.at n=28A152528
- Records in A139251.at n=42A152768
- Triangle read by rows: let t1(n,k)=Sum[(-1)^j Binomial[n + 1, j](k + 1 - j)^n, {j, 0, k + 1}]; then T(n,m)=2*t1(n + 1, k) - (m! - n! + (-m + n)!).at n=33A155452
- Triangle read by rows: let t1(n,k)=Sum[(-1)^j Binomial[n + 1, j](k + 1 - j)^n, {j, 0, k + 1}]; then T(n,m)=2*t1(n + 1, k) - (m! - n! + (-m + n)!).at n=30A155452