4572
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
- 2
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 11648
- Proper Divisor Sum (Aliquot Sum)
- 7076
- 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
- 1512
- Möbius Function
- 0
- Radical
- 762
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 33
- 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
- Generalized sum of divisors function.at n=45A002132
- Coordination sequence T2 for Zeolite Code STI.at n=46A008235
- a(n) = floor( n*(n-1)*(n-2)/29 ).at n=52A011911
- Length of n-th term of A022482.at n=27A022483
- Numbers m such that uphi(sigma(m)) = 2m, where the unitary phi function (A047994) is defined by: if x = p1^r1*p2^r2*p3^r3*... then uphi(x) = (p1^r1 - 1)*(p2^r2 - 1)*(p3^r3 - 1)*...at n=7A030165
- Records for sum of proper divisors function A001065.at n=45A034091
- Number of partitions of n such that cn(0,5) = cn(2,5) < cn(1,5) <= cn(3,5) = cn(4,5).at n=69A036856
- Number of partitions satisfying cn(0,5) + cn(2,5) + cn(3,5) <= cn(1,5) and cn(0,5) + cn(2,5) + cn(3,5) <= cn(4,5).at n=40A039908
- Numbers whose base-5 representation contains exactly two 1's and three 2's.at n=35A045228
- e-perfect numbers: numbers k such that the sum of the e-divisors (exponential divisors) of k equals 2*k.at n=40A054979
- Sum of composite numbers up to n is palindromic.at n=9A057959
- Number of primes between n^4 and (n+1)^4.at n=24A061235
- n - 5^k is a prime for all k > 0 and n > 5^k.at n=50A067529
- The concatenation of n with n-1 and n with n+1 both yield primes (twin primes).at n=39A068700
- Sum of numbers that can be written as t*n + u*(n+1) for nonnegative integers t,u in exactly one way.at n=7A076454
- Triangle T(n,k) (n >= 2, 1 <= k <= n) read by rows: (1/2) times number of linearly inducible orderings of n points in k-dimensional Euclidean space.at n=31A087644
- Triangle read by rows: T(n,k) is the number of ordered trees with n edges and k branches.at n=52A091187
- Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n having k peaks at even height.at n=47A091869
- Triangle read by rows: a(n,k) = C(n,k)*(2^(n-k) - 1) for k<n, a(n,k) = 0 for k >= n, where k=0..max(n-1,0).at n=39A091913
- G.f.: A(x) = Product_{n>=0} (1+a(n)*x^(n+1))^2 = Sum_{n>=0} a(n)*x^n.at n=7A093635