15810
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
- 32
- Divisor Sum
- 41472
- Proper Divisor Sum (Aliquot Sum)
- 25662
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3840
- Möbius Function
- -1
- Radical
- 15810
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 5
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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 190
- 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
- Smallest number m such that when A051953 is applied n times to m the result is neither a power of 2 nor 0.at n=16A053476
- a(n) = Sum_{d|6} phi(d)*n^(6/d).at n=5A054605
- a(n) = Sum_{d|n} phi(d)*5^(n/d).at n=6A054612
- Triangle T(n,k) = Sum_{d|n} phi(d)*k^(n/d).at n=19A054618
- Smallest number m such that the trajectory of m under iteration of cototient function[=A051953] contains exactly n distinct numbers (including m and the fixed point=0). Or: the required number of iterations[=operations,transitions] is n-1.at n=23A098197
- n*(n-1)*(n^2-n+4)/6.at n=18A103290
- Number of dihedral primes with n digits.at n=12A134997
- Composites one larger than a prime, with exactly five distinct prime factors.at n=30A136154
- a(n) = 17*n*(n+1).at n=30A173308
- a(n) = n*(14*n - 11).at n=34A195021
- a(n) = (n-2)*(14*n-39) for n > 2, otherwise a(n) = n.at n=36A195030
- a(n) = (n+1)*(n-2)*(n-3)/2.at n=31A212343
- Degrees of irreducible representations of orthogonal group O10+(2).at n=14A214472
- Steffensen's bracket function [n,n-3].at n=16A241170
- Triangle T(n,k) read by rows: T(n,k) is the number of closed lambda-terms of size n with size 0 for the variables and k abstractions.at n=32A259356
- a(n) = k if the first appearance of n in A077618 is at index k, or 0 if k does not appear in A077618.at n=35A291056
- a(n) is the smallest number k with n prime factors such that p + k/p is prime for every prime p | k.at n=4A294925
- Number of nonisomorphic proper colorings of partition multicycle graph using six colors.at n=43A298266
- Squarefree numbers k such that the sum of the distinct prime factors of k is twice the difference between the largest and the smallest prime factors of k.at n=18A324210
- Perimeters of more than one primitive 120-degree integer triangle.at n=10A350047