11826
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 20
- Divisor Sum
- 26862
- Proper Divisor Sum (Aliquot Sum)
- 15036
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3888
- Möbius Function
- 0
- Radical
- 438
- Omega Function (Ω)
- 6
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 81
- 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
- Numbers k such that 11*2^k - 1 is prime.at n=13A001772
- Numbers k such that k divides 2^(k+1) - 2.at n=34A014741
- Positive integers n such that n | (2^n + n/2 - 1).at n=32A015942
- Multiplicity of highest weight (or singular) vectors associated with character chi_77 of Monster module.at n=37A034465
- Numbers k such that k^2 contains exactly 9 different digits.at n=5A054037
- Numbers whose square is a zeroless pandigital number (i.e., use the digits 1 through 9 once).at n=0A071519
- Starting term of the smallest n-chain of numbers whose squares are permutations of the same digits.at n=28A085546
- Riordan array (1/(1+x), x(1-x)/(1+x)^2).at n=59A110511
- Riordan array (1/(1-x),x(1+x)/(1-x)^2).at n=59A114188
- Number of ternary trees with n edges and having no vertices of degree 1. A ternary tree is a rooted tree in which each vertex has at most three children and each child of a vertex is designated as its left or middle or right child.at n=10A120984
- Multiples of 18 containing a 18 in their decimal representation.at n=27A121038
- Terms of A068563 that are not terms of A124240.at n=46A124241
- Numbers whose square is a permutational number A134640.at n=34A134742
- Number of symmetry classes of 3 X 3 semimagic squares with distinct positive values < n.at n=16A173723
- Triangle T(n,k) read by rows: the coefficient [x^k] of the product_{s=1..n} (x+16*cos(s*Pi/(2n+1))^4), 0<=k<=n.at n=38A179837
- Let i be in {1,2,3,4} and let r >= 0 be an integer. Let p = {p_1, p_2, p_3, p_4} = {-2,0,1,2}, n=3*r+p_i, and define a(-2)=0. Then a(n)=a(3*r+p_i) gives the quantity of H_(9,4,0) tiles in a subdivided H_(9,i,r) tile after linear scaling by the factor Q^r, where Q=sqrt(x^2-1) with x=2*cos(Pi/9).at n=35A187502
- Expansion of (5-8*x-15*x^2+4*x^3+4*x^4)/(1-2*x-5*x^2+2*x^3+4*x^4+x^5).at n=8A189236
- Triangle of coefficients of polynomials u(n,x) jointly generated with A112351; see the Formula section.at n=61A209414
- Number of compositions of n into distinct parts with exactly one descent.at n=31A241720
- Depth of Pascal's triangle such that the number of elements in the triangle is a factor of the sum of the elements.at n=16A272934