5525
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 7812
- Proper Divisor Sum (Aliquot Sum)
- 2287
- 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
- 3840
- Möbius Function
- 0
- Radical
- 1105
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 129
- 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
- no
- Odd
- yes
Appears in sequences
- Number of points of norm <= n^2 in square lattice.at n=42A000328
- Square pyramidal numbers: a(n) = 0^2 + 1^2 + 2^2 + ... + n^2 = n*(n+1)*(2*n+1)/6.at n=25A000330
- Smallest number that is the sum of 2 squares (allowing zeros) in exactly n ways.at n=5A000446
- Smallest number that is the sum of 2 squares in at least n ways.at n=5A000448
- The coding-theoretic function A(n,4,4).at n=48A001843
- Least hypotenuse of n distinct Pythagorean triangles.at n=22A006339
- a(n) = binomial(n+3, 3)/4 for odd n, n*(n+2)*(n+4)/24 for even n.at n=49A006918
- a(n) is the smallest number greater than a(n-1) that is expressible as the sum of two squares in more ways than a(n-1).at n=4A007511
- Molien series of 4-dimensional representation of cyclic group of order 4 over GF(2) (not Cohen-Macaulay).at n=49A008610
- a(n) = floor(n*(n-1)*(n-2)/24).at n=52A011842
- Odd square pyramidal numbers.at n=12A015221
- Least positive integer that is the sum of two squares of positive integers in exactly n ways.at n=5A016032
- Smallest k such that circle x^2 + y^2 = k passes through exactly 4n integer points.at n=11A018782
- Number of isotropic subspaces of a 2n-dimensional unitary space over GF(4).at n=2A018925
- Pseudoprimes to base 18.at n=30A020146
- a(n) = s(1)*s(n) + s(2)*s(n-1) + ... + s(k)*s(n+1-k), where k = floor((n+1)/2), s = (odd natural numbers).at n=24A024598
- Every suffix prime and no 0 digits in base 6 (written in base 6).at n=43A024781
- Numbers that are the sum of 2 nonzero squares in exactly 6 ways.at n=0A025289
- Numbers that are the sum of 2 nonzero squares in 4 or more ways.at n=27A025295
- Numbers that are the sum of 2 nonzero squares in 5 or more ways.at n=0A025296