16613
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
- 4
- Divisor Sum
- 17100
- Proper Divisor Sum (Aliquot Sum)
- 487
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16128
- Möbius Function
- 1
- Radical
- 16613
- 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
- Multiplicity of highest weight (or singular) vectors associated with character chi_79 of Monster module.at n=39A034467
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 17.at n=19A051982
- Trajectory of n under the Reverse and Add! operation carried out in base 2 does not reach a palindrome and (presumably) does not join the trajectory of any term m < n.at n=36A075252
- a(n) = smallest k such that the base-2 Reverse and Add! trajectory of A075252(n) joins the trajectory of k.at n=36A092211
- a(n) = a(n-1) + a(floor(n/2)) + a(ceiling(n/2)).at n=33A131205
- a(n) = least m such that sum of m reciprocal primes starting with n-th prime is >1.at n=21A137368
- Number of multisets {1^k1, 2^k2, ..., n^kn}, ki >= 0, with the sum of reciprocals <= 1.at n=12A212658
- Number of partitions p of n such that max(p)-min(p) = 7.at n=43A218570
- Number of typable lambda terms of size n with size 0 for the variables.at n=22A236393
- Expansion of f(-x^8)^2 / f(-x) in powers of x where f() is a Ramanujan theta function.at n=39A260164
- Solution (a(n)) of the complementary equation a(n) = 2*a(n-1) - a(n-2) + b(n-2); see Comments.at n=43A305329
- Numerators of the partial alternating sums of the reciprocals of the sum of divisors function (A000203).at n=13A357845
- a(n) = (n - 1) * Sum_{k=2..n} A000010(k).at n=37A385682
- a(n) = Sum_{k=0..floor(n/3)} 2^k * binomial(2*n-4*k+1,2*k+1).at n=11A387628