15666
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 35904
- Proper Divisor Sum (Aliquot Sum)
- 20238
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4464
- Möbius Function
- 1
- Radical
- 15666
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 58
- 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
- Numbers whose base-5 representation contains exactly three 0's and three 1's.at n=14A045172
- Numbers with exactly 4 distinct palindromic prime factors.at n=36A046402
- Beastly (or hateful) numbers: numbers containing the string 666 in their decimal expansion.at n=24A051003
- Number of character table entries of the symmetric group S_n which are < 0.at n=15A051748
- a(n) = (n+(n+1)) + (n*(n+1)) + (n^(n+1)).at n=5A138748
- 6 times centered hexagonal numbers: 18*n*(n+1) + 6.at n=29A164016
- Number of benzenoid graphs with n hexagonal faces and forcing number 0.at n=7A256981
- Numbers n such that A002088(n) < 3n^2/Pi^2.at n=24A285022
- Square array A(n, k) read by descending antidiagonals, where column k is the expansion of the e.g.f. exp(k*x)/(2 - exp(x)).at n=60A292915
- a(n) = n! * [x^n] exp(n*x)/(2 - exp(x)).at n=5A292916
- Number of free pure symmetric multifunctions with leaves a multiset whose multiplicities are the integer partition with Heinz number n.at n=34A317655
- Triangle read by rows, T(n, k) is the determinant of the matrix [s(n,k), s(n,k+1); s(n+1,k), s(n+1,k+1)] where s is the triangle A110440 of little Schroeder numbers.at n=33A321187
- a(n) = Sum_{k=1..n} k^2 * n^(n-k).at n=6A368524