13390
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 26208
- Proper Divisor Sum (Aliquot Sum)
- 12818
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4896
- Möbius Function
- 1
- Radical
- 13390
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 45
- 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) = dot_product(n,n-1,...2,1)*(5,6,...,n,1,2,3,4).at n=34A026060
- Expansion of 1/((1-3x)(1-9x)(1-10x)(1-12x)).at n=3A028106
- Starting positions of strings of 3 0's in the decimal expansion of Pi.at n=8A050202
- a(n) is the starting position of the first occurrence of a string of at least n '0's in the decimal expansion of Pi.at n=3A050279
- Number of 3-element intersecting families whose union is an n-element set.at n=5A053153
- Nonsquares which are the product of two numbers with the same digits (leading zeros are forbidden).at n=38A072443
- a(1)=1, a(n+1) = a(n) + spf(Sum_{i=1..n} a(i)), where spf=A020639 (smallest prime factor).at n=22A080180
- Starting positions of strings of four 0's in the decimal expansion of Pi.at n=0A083598
- Radius of inscribed circle within primitive Pythagorean triangles having legs that add up to a square, sorted on hypotenuse.at n=37A089551
- Index of first occurrence of exactly n consecutive zeros in a row in the decimal expansion of Pi.at n=3A096764
- Diagonal sums of number triangle A113582.at n=25A154324
- Triangular array, T(n,k) = s(n,k) + s(n,n-k), where s(n,k) are the Stirling numbers of the first kind.at n=38A154843
- Triangular array, T(n,k) = s(n,k) + s(n,n-k), where s(n,k) are the Stirling numbers of the first kind.at n=42A154843
- Array a(n,m) read by descending antidiagonals giving the number of intervals in a generalized Tamari lattice of m-ballot paths of size n.at n=31A255918
- Numbers n such that T(n) + T(n+1) + ... + T(n+24) is a square, where T = A000217 (triangular numbers).at n=7A257708
- Row sums of A232642, when seen as a triangle read by rows.at n=8A257956
- Magic sums of 4 X 4 magic squares composed of squares.at n=22A271580
- Expansion of Sum_{k>=2} x^Fibonacci(k)/(1 - x^Fibonacci(k)) / Product_{k>=2} (1 - x^Fibonacci(k)).at n=34A281689
- Number of squares in triangle-shaped polyominoes obtained by adding three identical polyominoes to the previous one, starting with one L-tetromino.at n=7A282389
- Number of strict trees of weight n with distinct leaves.at n=23A300352