8568
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 48
- Divisor Sum
- 28080
- Proper Divisor Sum (Aliquot Sum)
- 19512
- 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
- 2304
- Möbius Function
- 0
- Radical
- 714
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 171
- Smith Number
- yes
- 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
- Binomial coefficients C(n,5).at n=18A000389
- a(n) = n! * (n + 1 + 2*Sum_{k=1...n} 1/k).at n=6A000775
- Product of Fibonacci and Pell numbers.at n=7A001582
- Binomial coefficient C(2n,n-4).at n=5A004310
- a(n) = binomial(3*n, n - 1).at n=5A004319
- Number of exterior points formed by extending diagonals of n-gon in general position.at n=15A005701
- a(n) = floor(n*(n+2)*(2*n-1)/8).at n=31A007518
- 12-dimensional centered tetrahedral numbers.at n=5A008506
- Binomial coefficient C(18,n).at n=13A010934
- Binomial coefficient C(18,n).at n=5A010934
- a(n) = binomial(n,13).at n=5A010966
- a(n) = floor( n*(n-1)*(n-2)/5 ).at n=36A011887
- a(n) = ((b(n)-1)+sqrt(3*b(n)^2-4*b(n)+1))/2, where b(n) is A011922(n).at n=4A011916
- Duplicate of A009655.at n=7A012268
- Expansion of e.g.f. arctan(arcsinh(x) * exp(x)).at n=7A012588
- Triangular array formed from even elements to right of middle of rows of Pascal's triangle.at n=41A014476
- Number of compositions of n into 6 ordered relatively prime parts.at n=13A023031
- a(n) = integer nearest a(n-1)/(sqrt(7) - 2), where a(1) = 1.at n=20A024567
- a(n) = s(n+3)/3, where s is A024737.at n=8A024738
- Binomial coefficients: C(n,k), 5 <= k <= n-5, sorted.at n=27A024749