4489
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 3
- Divisor Sum
- 4557
- Proper Divisor Sum (Aliquot Sum)
- 68
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4422
- Möbius Function
- 0
- Radical
- 67
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 1
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- yes
- 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
- 90
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- no
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- yes
- Achilles Number
- no
- Perfect Power
- yes
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Squares that are not the sum of 2 nonzero squares.at n=40A000548
- Squares of primes.at n=18A001248
- a(1) = a(2) = 1, a(3) = 4; thereafter a(n) = a(n-1) + a(n-3).at n=21A001609
- Number of permutations of (1,...,n) having n-3 inversions (n>=3).at n=7A001893
- Sum of squares of odd primes dividing n.at n=66A005066
- Sum of squares of primes = 1 mod 3 dividing n.at n=66A005071
- Sum of squares of primes = 3 mod 4 dividing n.at n=66A005083
- Coordination sequence T4 for Zeolite Code AFO.at n=44A008018
- Coordination sequence T2 for Zeolite Code MEL.at n=43A008151
- Numbers m such that phi(m) * sigma(m) + k^2 is not a square for any k.at n=23A015713
- Odd squares: a(n) = (2n+1)^2. Also centered octagonal numbers.at n=33A016754
- a(n) = (3*n+1)^2.at n=22A016778
- a(n) = (4n + 3)^2.at n=16A016838
- a(n) = (5*n + 2)^2.at n=13A016874
- a(n) = (6*n + 1)^2.at n=11A016922
- a(n) = (7*n + 4)^2.at n=9A017030
- a(n) = (8n + 3)^2.at n=8A017102
- a(n) = (9*n + 4)^2.at n=7A017210
- a(n) = (10*n + 7)^2.at n=6A017354
- a(n) = (11*n+1)^2.at n=6A017402