16817
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17136
- Proper Divisor Sum (Aliquot Sum)
- 319
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16500
- Möbius Function
- 1
- Radical
- 16817
- 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
- 66
- 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
- Numbers k such that k*2^m+1 are composites for all exponents m in the range 0<=m<=k.at n=32A061153
- a(n) = 10*n^2 + 7.at n=41A061722
- Smaller terms in the pairs of numbers (a < b) in the sequence {a,b}-> {Max[{a,b}]-Min[{a,b}],k*Min[{a,b}]} with k=3 and the first pair {a=1,b=2}. See A075256.at n=48A075257
- a(n) = floor(Pi^(n/2)).at n=17A102475
- Nearest integer to the n-th root of e leading to a generalized closed form for Zeta(s).at n=23A108925
- Semiprimes p such that next semiprime after p is p+20.at n=4A217335
- Number of permutations p of [n] such that 0p has a nonincreasing jump sequence beginning with eight.at n=3A292174
- Number of compositions of n whose standard factorization into Lyndon words has all strict compositions as factors.at n=18A299023
- Number of nXn 0..1 arrays with every element unequal to 0, 2, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero.at n=4A316372
- Number of nX5 0..1 arrays with every element unequal to 0, 2, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero.at n=4A316373
- T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero.at n=40A316376
- Lexicographically earliest sequence of distinct positive integers such that a(n), a(n+1) and the product a(n)*a(n+1) have in common the substring n.at n=16A333933
- The number of unit squares enclosed by the rectangular spiral of which the n-th side has length prime(n).at n=33A356465