13220
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 27804
- Proper Divisor Sum (Aliquot Sum)
- 14584
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5280
- Möbius Function
- 0
- Radical
- 6610
- 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
- 50
- 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-dimensional partitions of n.at n=9A000334
- a(n) = floor(Gamma(n + 7/11)/Gamma(7/11)).at n=8A020053
- a(n) = floor(n^3 / e).at n=33A032636
- Numbers k such that k^256 + 1 is prime.at n=33A056995
- Sum of the second moments of all partitions of n with weights starting from 0.at n=14A066188
- Sequence A085188 shown in factorial base. (The longest prefix which can be shown with digits < 10.)at n=38A085187
- Numbers k such that k concatenated with itself gives the product of two numbers which differ by 9.at n=9A116162
- Numbers k such that k concatenated with k+8 gives the product of two numbers which differ by 7.at n=6A116215
- a(n) = 25*n^2 - 5.at n=22A158446
- Row sums of A163357 and A163359 divided by 4.at n=39A163477
- Number of 8-step S, NW and NE-moving king's tours on an n X n board summed over all starting positions.at n=6A187382
- Number of right triangles on a (n+1)X7 grid.at n=12A189811
- Smallest k such that k^(2^n) + 1 and (k+2)^(2^n) + 1 are both prime.at n=8A217993
- Number of 3Xn arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 3Xn array.at n=8A219854
- Number of (n+1)X(3+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or vertically, with no adjacent elements equal.at n=7A232401
- T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or vertically, with no adjacent elements equal.at n=47A232406
- Number of (n+1) X (n+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).at n=8A235281
- Number of partitions p of n such that median(p) <= mean(p).at n=34A240218
- Indices of primes in A214830.at n=12A244001
- Number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 1", based on the 5-celled von Neumann neighborhood.at n=57A269906