9220
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 19404
- Proper Divisor Sum (Aliquot Sum)
- 10184
- 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
- 3680
- Möbius Function
- 0
- Radical
- 4610
- Omega Function (Ω)
- 4
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 109
- 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
- Number of 4-colorings of cyclic group of order n.at n=11A007687
- Arrange digits of squares in descending order.at n=47A028908
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 48.at n=36A031546
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 48.at n=3A031726
- a(n) = (n - 1)*(n^2 + n - 1).at n=21A033445
- Triangle read by rows, the Bell transform of n!*binomial(5,n) (without column 0).at n=16A049411
- Open 3-dimensional ball numbers (version 3): a(n) is the number of integer points (i,j,k) contained in an open ball of diameter n, centered at (1/2,1/2,0).at n=26A053595
- Numbers k such that k + (largest digit of k)! is a square.at n=45A095927
- Slowest increasing sequence where the absolute difference between the last digit of a(n) and the first digit of a(n+1) equals 9.at n=34A101243
- Expansion of x^2*(1-x)*(x^2+x+1)*(x^6+x^3+1)/((2*x-1)*(2*x^9-x^6+x^3-1)).at n=15A111662
- Left border of triangle A137629.at n=28A137631
- Numbers k such that the number of digits d in k^2 is not prime and for each factor f of d the sum of the d/f digit groupings in k^2 of size f is a square.at n=30A153745
- Numbers k such that there are 8 digits in k^2 and for each factor f of 8 (1,2,4) the sum of digit groupings of size f is a square.at n=20A153746
- Numerator of Euler(n, 1/21).at n=4A156758
- a(n) = 16*n^2 + 4.at n=23A158444
- Number of -n..n arrays x(0..4) of 5 elements with zero sum, adjacent elements differing by more than one, and elements alternately increasing and decreasing.at n=7A200194
- Number of n X n 0..3 symmetric matrices with every element equal to one, two or three horizontal and vertical neighbors, and new values 0..3 introduced in lower triangle row major order.at n=4A210926
- The number of divisors d of n! such that d < A000793(n) (Landau's function g(n)) and the symmetric group S_n contains no elements of order d.at n=47A211391
- Equals one maps: number of 2 X n binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, diagonal and antidiagonal neighbors in a random 0..1 2 X n array.at n=9A220538
- Let m = n-th number not divisible by 3 (A001651); a(n) = position of m in A065075, or -1 if never appears in A065075.at n=26A230289