17225
domain: N
Properties
Digital Properties
- Digit Count
- 5
- 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
- 23436
- Proper Divisor Sum (Aliquot Sum)
- 6211
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12480
- Möbius Function
- 0
- Radical
- 3445
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 79
- 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 permutations of [n] with four inversions.at n=21A005287
- Consider pairs (k,m) such that k^2 begins with a 1 and when the 1 is changed to a 2 we again get a square, m^2; sequence gives values of m for primitive solutions.at n=2A018232
- Nearest integer to Gamma(n + 5/7)/Gamma(5/7).at n=8A020030
- a(n) = floor( Gamma(n+5/7)/Gamma(5/7) ).at n=8A020075
- s(n+3)/2, where s is A024735.at n=12A024736
- Numbers that are the sum of 2 nonzero squares in exactly 6 ways.at n=8A025289
- Numbers that are the sum of 2 nonzero squares in 5 or more ways.at n=13A025296
- Numbers that are the sum of 2 nonzero squares in 6 or more ways.at n=8A025297
- Numbers that are the sum of 2 distinct nonzero squares in exactly 6 ways.at n=8A025307
- Numbers that are the sum of 2 distinct nonzero squares in 5 or more ways.at n=11A025315
- Numbers that are the sum of 2 distinct nonzero squares in 6 or more ways.at n=8A025316
- a(n) = dot_product(1,2,...,n)*(6,7,...,n,1,2,3,4,5).at n=33A026046
- Expansion of (1+x^4*C)*C, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.at n=10A071742
- Sum of n-th antidiagonal of array in A081998.at n=19A082001
- Numbers m that are the hypotenuse of exactly 22 distinct integer-sided right triangles, i.e., m^2 can be written as a sum of two squares in 22 ways.at n=9A097103
- Indices for which A097344 differs from A097345.at n=3A134652
- RMS values of the RMS numbers: a(n) is the root mean square of the divisors of A140480(n).at n=15A141812
- a(n) = n^3 - n*(n+1)/2.at n=26A160378
- Number of reduced words of length n in the Weyl group A_24.at n=4A161524
- a(n) = 20*a(n-1) - 95*a(n-2) for n > 1; a(0) = 1, a(1) = 11.at n=4A163310