12537
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
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 20800
- Proper Divisor Sum (Aliquot Sum)
- 8263
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7128
- Möbius Function
- 0
- Radical
- 4179
- Omega Function (Ω)
- 4
- 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
- no
- 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
- no
- Odd
- yes
Appears in sequences
- Number of increasing rooted polygonal cacti (Husimi graphs) with n nodes.at n=7A035086
- Numbers k such that k divides the (right) concatenation of all numbers <= k written in base 15 (most significant digit on right).at n=13A061944
- Indices of primes in sequence defined by A(0) = 91, A(n) = 10*A(n-1) + 61 for n > 0.at n=10A101014
- Row sums of a scaled Legendre triangle.at n=7A110125
- Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 1 X 2 which is symmetric after a rotation by 180 degrees.at n=8A123763
- Numbers which are the sum of 3 cubes of distinct odd primes.at n=34A138853
- a(n) = 256*n^2 - n.at n=6A158010
- a(n) = 49*n^2 - 7.at n=15A158484
- Imbalance of the sum of parts of all partitions of n.at n=28A194797
- Numbers generated by recursive procedure a(n) = nozero(a(n-1) * 3), in which the function nozero(x) removes all zeros from x, starting with a(1) = 1.at n=31A243845
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 369", based on the 5-celled von Neumann neighborhood.at n=25A268503
- Number of Dyck paths of semilength n such that the number of peaks is strongly decreasing from lower to higher levels.at n=14A288141
- Number of compositions (ordered partitions) of the n-th prime into distinct prime parts.at n=20A331901
- a(n) = ((1 - sqrt(2))^n + (1 + sqrt(2))^n)*n/2.at n=9A364636