16517
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 16800
- Proper Divisor Sum (Aliquot Sum)
- 283
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16236
- Möbius Function
- 1
- Radical
- 16517
- 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
- 190
- 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 that are the sum of 7 positive 7th powers.at n=37A003374
- Composite numbers n such that k! == 1 (mod n) for some k > 2.at n=20A049048
- Integers k > 10577 such that the 'Reverse and Add!' trajectory of k joins the trajectory of 10577.at n=5A063434
- Least number k such that between k! and (k+1)! there are n powers of 2 (each interval includes (k+1)! but not k!).at n=14A084321
- Last term where no prime sums occur in A161190 in a 4-diagonal set of 24 terms.at n=6A161193
- G.f. A(x) satisfies: (A(x) + x*A'(x)) / (A(x) - x*A(x)^2) = Sum_{n>=0} binomial(2*n,n)^2*x^n.at n=5A232607
- a(n) = prime(n) * prime(2n).at n=22A319613
- Number of integer partitions of n > 0 where the maximum part minus the minimum part equals the length minus the number of distinct parts.at n=54A324516
- Nonprime Heinz numbers of multiples of triangular partitions, or of finite arithmetic progressions with offset 0.at n=31A325407
- Numbers that cannot be written as a difference of 11-smooth numbers.at n=34A326319
- Number of palindromes < 10^n whose squares are also palindromes.at n=40A343098
- G.f. A(x) satisfies: 1 = Sum_{n>=0} (-x)^n * A(x)^(2*n) * A(x*A(x)^n).at n=8A352854