4520
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 10260
- Proper Divisor Sum (Aliquot Sum)
- 5740
- 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
- 1792
- Möbius Function
- 0
- Radical
- 1130
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 20
- 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 Hamiltonian cycles in C_5 X P_n.at n=5A003731
- Place n equally-spaced points around a circle and join every pair of points by a chord; this divides the circle into a(n) regions.at n=19A006533
- 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 33.at n=18A031531
- a(n)=(s(n)+3)/9, where s(n)=n-th base 9 palindrome that starts with 6.at n=36A043077
- Number of 7-block tricoverings of an n-set.at n=1A060485
- Triangle T(n,k) of k-block tricoverings of an n-set (n >= 3, k >= 4).at n=11A060487
- Numbers of the form (10*a + b)^2 + (10*b + a)^2 with a and b less than 10, in numerical order.at n=21A061191
- Number of atoms in cluster of n layers around C_60.at n=10A063498
- Add column entries of the table with rows (1,2,0,0...), (0,3,4,5,0,0...), (0,0,6,7,8,9,0,0...), (0,0,0,10,11,12,13,14,0,0...), ...at n=29A064694
- Numbers k such that A068976(k) divides k.at n=45A069144
- Sum of terms in n-th group in A075352.at n=33A075356
- Binomial transform of floor(n/2)!.at n=10A081124
- a(n) = 5*(n^2 - n + 2)/2.at n=43A082450
- a(n) is the minimal number of nodes in a binary tree of height n.at n=48A102379
- Number of positive integers <= 10^n that are divisible by no prime exceeding 11.at n=7A107352
- n times n+7 gives the concatenation of two numbers m and m-6.at n=7A116250
- Total number of parts that appear exactly once in the partitions of n into odd parts.at n=46A116665
- Rectangular table, read by antidiagonals, where row n is equal to column 2 of matrix power A121412^(n+1) for n>=0.at n=40A121428
- Main diagonal of rectangular table A121428.at n=4A121429
- Number of subpartitions of partition P=[0,0,0,1,1,1,1,2,2,2,2,2,3,...], where P(n) = [(sqrt(8*n+25) - 5)/2].at n=22A121432