17128
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 32130
- Proper Divisor Sum (Aliquot Sum)
- 15002
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8560
- Möbius Function
- 0
- Radical
- 4282
- Omega Function (Ω)
- 4
- 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
- 27
- 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
- Expansion of e.g.f. tan(x)*tan(sinh(x)), even powers only.at n=4A009749
- 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 65.at n=34A031563
- One half of the number of Young tableaux with n cells whose shape is asymmetric.at n=11A067142
- Numbers k such that 12321*2^k + 1 is prime.at n=27A180924
- Number of 3-step knight's tours on an (n+2) X (n+2) board summed over all starting positions.at n=17A186852
- The Matula-Goebel numbers of the rooted trees that have palindromic Wiener polynomials.at n=20A198322
- Numbers that can be written as (k + sum of digits of k) for some k, then as (m + product of digits of m) for some m, also as (q * product of digits of q) for some q, and finally as (t * sum of digits of t) for some t.at n=26A337839
- Number of connected graphs with vertices labeled with positive integers summing to n.at n=8A340025
- Square array T(n,k), n >= 1, k >= 1, read by antidiagonals, where T(n,k) = Sum_{1 <= x_1, x_2, ..., x_k <= n} gcd(x_1, x_2, ..., x_k).at n=61A344479
- a(n) = Sum_{1 <= i, j, k, l, m <= n} gcd(i,j,k,l,m).at n=6A344524
- Expansion of 1 + Sum_{i>=1} Sum_{j>=1} x^(i*j) * Product_{k=1..i*j-1} (1+x^k).at n=51A373030
- Number of distinct possible binary ranks of integer partitions of n, where the binary rank of a partition y is given by Sum_i 2^(y_i-1).at n=48A373120
- Number of integer partitions of n having at most one permutation with all equal run-lengths.at n=43A383092