16408
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
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 35280
- Proper Divisor Sum (Aliquot Sum)
- 18872
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7008
- Möbius Function
- 0
- Radical
- 4102
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 3
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
- 40
- 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
- a(n) = Sum_{odd d|n} phi(d)*2^(n/d).at n=14A053636
- a(n) = Sum_{d|7} phi(d)*n^(7/d).at n=4A054606
- a(n) = Sum_{d|n} phi(d)*4^(n/d).at n=7A054611
- Triangle T(n,k) = Sum_{d|n} phi(d)*k^(n/d).at n=24A054618
- An Alexander sequence for the knot 8_5.at n=15A099846
- Self-convolution omits 1's at positions of triangular numbers less one.at n=28A105613
- Self-convolution of A105613.at n=21A105614
- Number of complete compositions of n.at n=15A107429
- Total area under all the level steps in all peakless Motzkin paths of length n (n>=0).at n=12A171849
- Number of length-n 0..6 arrays with no repeated value greater than the previous repeated value.at n=4A269433
- T(n,k)=Number of length-n 0..k arrays with no repeated value greater than the previous repeated value.at n=49A269435
- Number of length-5 0..n arrays with no repeated value greater than the previous repeated value.at n=5A269437
- Expansion of Product_{j>=1} (1 + j*(-1 + Product_{k>=1} (1 + k*x^k))^j).at n=8A307566
- a(n) = A327005(n, n).at n=9A327006
- 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=25A337839
- Maximum number of induced copies of the diamond graph K_{1,1,2} in an n-node graph.at n=29A352668
- Number of ways to write n as an ordered sum of seven positive Fibonacci numbers (with a single type of 1).at n=34A357694
- Expansion of (1/x) * Series_Reversion( x * ((1-x)^4-x^4) ).at n=5A369102
- Triangle read by rows: T(n, k) = n! * 3^k * hypergeom([-k], [-n], 2/3).at n=19A375600
- Square array A(n,k), n >= 1, k >= 1, read by antidiagonals downwards, where A(n,k) = -Sum_{d|n} phi(n/d) * (-k)^d.at n=51A382994