17249
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17664
- Proper Divisor Sum (Aliquot Sum)
- 415
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16836
- Möbius Function
- 1
- Radical
- 17249
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 141
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- 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
- a(n) = (n + 3)*(n^2 + 6*n + 2)/6.at n=44A005286
- Number of intersections of diagonals in the interior of a regular n-gon.at n=27A006561
- Numerators of Sum_{k=1..n} 1/lcm(n,k).at n=11A074947
- Number of distinct values obtained when each of the operators # in the expression 1#2#3#...#n is replaced by + (add) or x (multiply) in all possible ways, for n=1,2,3,...at n=15A138651
- a(n) = 22*n^2 + 1.at n=28A158537
- a(n) is the smallest positive multiple of 2n-1 that contains the binary representation of n in its binary representation and that is a palindrome when written in binary.at n=23A158789
- Number of reduced words of length n in the Weyl group A_46.at n=3A161691
- Number of reduced words of length n in the Weyl group B_24.at n=4A161931
- Number of reduced words of length n in the Weyl group D_24.at n=4A162366
- Sum of all odd-indexed parts minus the sum of all even-indexed parts of all partitions of n, with the parts written in nondecreasing order.at n=38A194714
- Number of -n..n arrays x(0..3) of 4 elements with zero sum, and adjacent elements not both strictly positive and not both strictly negative.at n=21A199899
- Number of edges in the Hasse diagram of the poset of conjugacy classes of subgroups of the symmetric group.at n=11A218925
- Triangle T(n,k) giving the number of terms of A219666 which have n digits (A084558) in their factorial base expansion and whose most significant digit (A099563) in that base is k.at n=39A230420
- Triangle A230420 transposed.at n=41A230421
- L.g.f.: log(Product_{k>=1} (1 + x^k/(1 - x))) = Sum_{k>=1} a(k)*x^k/k.at n=51A307761
- Odd composite integers m such that U(m)^2 == 1 (mod m) and V(m) == 5 (mod m), where U(m)=A004254(m) and V(m)=A003501(m) are the m-th generalized Lucas and Pell-Lucas numbers of parameters a=5 and b=1, respectively.at n=33A337779
- Odd composite integers m such that A004254(m-J(m,21)) == 0 (mod m) and gcd(m,21)=1, where J(m,21) is the Jacobi symbol.at n=34A340098
- a(n) is the number of distinct solution sets to the quadratic equations u*x^2 + v*x + w = 0 with integer coefficients u, v, w, abs(u) + abs(v) + abs(w) <= n having a negative discriminant.at n=44A381710