15630
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 37584
- Proper Divisor Sum (Aliquot Sum)
- 21954
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4160
- Möbius Function
- 1
- Radical
- 15630
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 133
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- 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
- a(n) = floor(n*phi^13), where phi is the golden ratio, A001622.at n=30A004928
- a(n) = round(n*phi^13), where phi is the golden ratio, A001622.at n=30A004948
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 50.at n=4A031728
- Sums of two distinct powers of 5.at n=16A038474
- T(n,n-4), array T as in A038792.at n=25A038794
- Theta series of D8 lattice with respect to midpoint of edge.at n=12A045820
- Sums of two powers of 5.at n=22A055237
- Operation count to create all permutations of n distinct elements using the "streamlined" version of Algorithm L (lexicographic permutation generation) from Knuth's The Art of Computer Programming, Vol. 4, chapter 7.2.1.2. Sequence gives number of interchanges in reversal step.at n=6A079756
- a(n) = A061419(n) - A002379(n).at n=25A083198
- Expansion of 1/((1-5*x)*(1-x^5)).at n=6A083590
- a(n) = n^3 + 5.at n=25A084381
- Square array T(r,m) read by antidiagonals: number of cyclically reduced words of length m in F_r.at n=33A104000
- a(n) = p + p^(p+1), where p = prime(n).at n=2A104128
- Array read by antidiagonals: a(n,k) = number of k-colorings of a circle of n nodes (n >= 1, k >= 1).at n=60A106512
- Number of functions f: {1, 2, ..., n} --> {1, 2, ..., n} such that f(1) != f(2), f(2) != f(3), ..., f(n-1) != f(n), f(n) != f(1).at n=4A118537
- a(n) = n^6 + n.at n=5A131472
- a(n) = 25*n^2 + 5.at n=24A158445
- a(n) = 5^n + 5.at n=6A178676
- G.f.: exp( Sum_{n>=1} 2^A090740(n) * x^n/n ) where A090740(n) = highest exponent of 2 in 3^n-1.at n=24A182000
- Central coefficients of the Riordan matrix A104259.at n=5A190738