13050
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 36270
- Proper Divisor Sum (Aliquot Sum)
- 23220
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3360
- Möbius Function
- 0
- Radical
- 870
- Omega Function (Ω)
- 6
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 138
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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) = n*(n+1)^2/2.at n=29A006002
- a(n) = n*(31*n + 1)/2.at n=29A022289
- Number of nonempty subsets of {1,2,...,n} in which exactly 1/3 of the elements are <= n/2.at n=17A047161
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= n/2.at n=17A047162
- Least k for which the integers Floor(k/(m*(m+1))) for m=1,2,...,n are distinct.at n=33A054061
- Generalized Catalan numbers 5*x*A(x)^2 -A(x) +1 -4*x=0.at n=5A068767
- Numbers k such that the sum of factorials of the digits of k equals the sum of the primes from the smallest prime factor of k to the largest prime factor of k.at n=4A074256
- Sum of first n perfect powers.at n=40A076408
- Indices of primes in sequence defined by A(0) = 43, A(n) = 10*A(n-1) - 17 for n > 0.at n=16A101716
- Numbers k for which nontrivial positive magic squares of exactly 9 different orders with magic sum k exist. For a definition of nontrivial positive magic squares, see A125005.at n=23A125016
- Numbers n that raised to the powers from 1 to k (with k>=1) are multiple of the sum of their digits (n raised to k+1 must not be a multiple). Case k=10.at n=20A135195
- a(1)=1, a(n)=a(n-1)+n^3 if n odd, a(n)=a(n-1)+ n^0 if n is even.at n=17A140152
- Numbers k such that lambda(k) = lambda(k+1).at n=19A173695
- Fast "exotic addition" a o b = [ a[1]+b[1], a[1]*b[2]+a[2]*b[1] ].at n=30A175841
- Number of arrangements of n indistinguishable balls in n boxes with the maximum number of balls in any box equal to n-2.at n=27A180292
- Left edge of the triangle A045975.at n=29A204556
- Denominators of rationals with e.g.f. D(4,x), a Debye function.at n=56A227574
- Number of n X 4 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.at n=6A228478
- Number of nX7 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.at n=3A228481
- T(n,k)=Number of nXk binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.at n=48A228482