16490
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 31752
- Proper Divisor Sum (Aliquot Sum)
- 15262
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6144
- Möbius Function
- 1
- Radical
- 16490
- 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
- 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
- yes
- Odd
- no
Appears in sequences
- a(n+1) = a(n) + n (if n is odd), a(n+1) = a(n) * n (if n is even).at n=10A047904
- Engel expansion of zeta(3) = 1.20206... .at n=6A053980
- Given the infinite continued fraction i+(i/(i+(i/(i+...)))), where i is the square root of (-1), this is the denominator of the imaginary part of the convergents.at n=23A091809
- a(n) = smallest k such that the base-2 Reverse and Add! trajectory of A075252(n) joins the trajectory of k.at n=34A092211
- Triangle T(n,k) for A(x)^k=sum(n>=k T(n,k)*x^n), where o.g.f. A(x) satisfies A(x)=(1+x*A(x)^3)/(1-x*A(x)^3).at n=40A187920
- a(n) = n*(3*n^2 + 6*n + 1).at n=17A196507
- Numbers that can be represented as a sum of two distinct nontrivial prime powers in three or more ways.at n=17A225104
- Numbers which are the sum of two squared primes in exactly three ways (ignoring order).at n=5A226562
- Numbers k that are the product of four distinct primes such that x^2+y^2 = k has integer solutions.at n=25A248712
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 793", based on the 5-celled von Neumann neighborhood.at n=25A273566
- a(n) = [x^n] Product_{k=1..n} 1/((1 - x)^k * (1 - x^k)).at n=5A292424
- Number of permutations of [n] avoiding {4231, 2143, 1234}.at n=14A294708
- Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = n! * Sum_{j=0..n} k^(n-j) * (n-j)^j/j!.at n=33A351761
- Expansion of e.g.f. 1/(1 - 2*x*exp(x)).at n=5A351762
- Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,0) = 0^n and T(n,k) = k * Sum_{r=0..n} binomial(n,r) * binomial(3*n+r+k,n)/(3*n+r+k) for k > 0.at n=49A378238