15587
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 18480
- Proper Divisor Sum (Aliquot Sum)
- 2893
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12960
- Möbius Function
- -1
- Radical
- 15587
- Omega Function (Ω)
- 3
- 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
- 102
- 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
- no
- Odd
- yes
Appears in sequences
- Numerators of generalized Bernoulli numbers.at n=13A006569
- Number of fixed n-celled lattice animals in the b.c.c. lattice (8 nearest neighbors), or connected truncated octahedra, or vertex-connected cubes.at n=5A039741
- Number of nonempty subsets of {1,2,...,n} in which exactly 5/6 of the elements are <= (n-2)/3.at n=36A048026
- Number of nonempty subsets of {1,2,...,n} in which exactly 5/6 of the elements are <= (n-3)/3.at n=36A048037
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, 0), (0, 1, -1), (1, 0, -1), (1, 0, 0)}.at n=11A148040
- Sum of all numbers from 2*n-1 up to prime(n).at n=44A161626
- Monotonic ordering of nonnegative differences 3^i-4^j, for 40>= i>=0, j>=0.at n=34A192147
- Monotonic ordering of nonnegative differences 3^i-8^j, for 40>= i>=0, j>=0.at n=25A192155
- Displacement under constant discrete unit surge.at n=11A207361
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>n.at n=25A211640
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>=n.at n=25A211641
- Irregular array read by rows: A(n,k) = number of first coronas of a fixed rhombus r_{n,k} with characteristics of n-fold rotational symmetry in the Euclidean plane, n>=2, 1<=k<=floor(n/2), as explained below.at n=4A233332
- Number of odd chordless cycles in the n-Andrásfai graph.at n=11A301771
- Expansion of Sum_{k>=0} x^k * Product_{j=1..k} (1 + x^j)^j.at n=24A306731
- a(n) is the A-sequence for the Riordan matrix R = (1/(1- x^2 - x^3), x/(1 - x^2 - x^3)) from A104578.at n=17A319202
- Smallest number k with A355915(k) = n.at n=26A356792