16365
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 26208
- Proper Divisor Sum (Aliquot Sum)
- 9843
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8720
- Möbius Function
- -1
- Radical
- 16365
- 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
- 128
- 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
- Number of 2n-bead balanced binary necklaces of fundamental period 2n, equivalent to reversed complement; also Dirichlet convolution of b_n=2^(n-1) with mu(n); also number of components of Mandelbrot set corresponding to Julia sets with an attractive n-cycle.at n=14A000740
- Number of Barlow packings with group P63/mmc(S) that repeat after 4n layers.at n=14A011946
- Number of 2n-bead balanced binary necklaces of fundamental period 2n which are equivalent to their reverse, complement and reversed complement.at n=30A045683
- Triangle of numbers related to Eulerian numbers.at n=38A046803
- 4n^2+1, 2n^2+1, 2n^2-1 are all prime.at n=37A055755
- Number of primitive (aperiodic) word structures of length n which contain exactly two different symbols.at n=14A056278
- McKay-Thompson series of class 28a for Monster.at n=33A058610
- Numbers m such that [A070080(m), A070081(m), A070082(m)] is a right integer triangle.at n=23A070136
- Numbers k such that [A070080(k), A070081(k), A070082(k)] is a right integer triangle with relatively prime side lengths.at n=8A070137
- Duplicate of A011946.at n=14A195095
- Number of partitions p of n such that 3*min(p) is a part of p.at n=38A238590
- T(n,k)=Number of nXk arrays of permutations of 0..n*k-1 with rows nondecreasing modulo 6 and columns nondecreasing modulo 7.at n=23A264862
- Number of 3Xn arrays of permutations of 0..n*3-1 with rows nondecreasing modulo 6 and columns nondecreasing modulo 7.at n=4A264864
- Numbers k such that 4*10^k - 57 is prime.at n=23A281642
- The number of partitions of n which represent Chomp positions with Sprague-Grundy value 8.at n=56A284781
- Number of strings of length n from a 3-symbol alphabet (A,B,C, say) containing at least one "A" and at least two "B"s.at n=6A309000
- a(n) = Sum_{d|n, gcd(d, n/d) = 1} (-1)^omega(n/d) * 2^(d-1).at n=14A343440
- G.f. A(x) satisfies: x = Sum_{n=-oo..+oo} (-1)^n * x^(n*(n+1)/2) * A(x)^n.at n=8A355351
- a(n) = A269795(n)/2.at n=14A365162