8820
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 54
- Divisor Sum
- 31122
- Proper Divisor Sum (Aliquot Sum)
- 22302
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2016
- Möbius Function
- 0
- Radical
- 210
- Omega Function (Ω)
- 7
- 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
- 47
- 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) = (2*n)!*(2*n+1)! /((n+1)! *n!^3).at n=4A000894
- Number of walks on square lattice. Column y=1 of A052174.at n=8A005559
- Number of walks of length n on square lattice, starting at origin, staying in first quadrant.at n=8A005566
- Expansion of e.g.f.: cos(log(1+x)^2).at n=7A009035
- Expansion of e.g.f.: sech(log(x+1)*log(x+1)).at n=7A012274
- a(n) = n*(11*n+1)/2.at n=40A022269
- Duplicate of A022269.at n=39A026817
- Expansion of 1/((1-5x)(1-6x)(1-9x)(1-10x)).at n=3A028174
- Number of permutations of an n-set containing a 4-cycle.at n=8A029571
- Intermediate edge b of smallest (measured by the longest edge) primitive Euler bricks (a, b, c, sqrt(a^2 + b^2), sqrt(b^2 + c^2), sqrt(a^2 + c^2) are integers).at n=25A031174
- Every run of digits of n in base 14 has length 2.at n=39A033012
- a(n) = 5*n^2.at n=42A033429
- Decimal part of n-th root of a(n) starts with digit 4.at n=25A034081
- a(n) = n^3 - n^2.at n=21A045991
- a(n) = (2n-1)*(2n-1)!/n.at n=3A052145
- Triangle of numbers arising in enumeration of walks on square lattice.at n=46A052174
- Expansion of e.g.f.: -x^2*(log(1-x))^3.at n=7A052765
- Triangle T(s,t), s >= 1, 1 <= t <= s (see formula line).at n=33A059836
- Numbers k such that sigma (x) = k has exactly 12 solutions.at n=12A060676
- Square array read by antidiagonals of number of length k walks on an n-dimensional hypercubic lattice starting at the origin and staying in the nonnegative part.at n=57A064044