16309
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
- 4
- Divisor Sum
- 16704
- Proper Divisor Sum (Aliquot Sum)
- 395
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15916
- Möbius Function
- 1
- Radical
- 16309
- 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
- Coordination sequence for MgZn2, Mg position.at n=32A009939
- a(n) = floor( n*(n-1)*(n-2)*(n-3)/22 ).at n=26A011932
- Numbers n such that phi(n + 1) | sigma(n) for n congruent to 1 (mod 3).at n=36A015817
- a(n) = d(n)/2, where d = A026040.at n=43A026041
- Numbers whose base-5 representation has exactly 7 runs.at n=23A043607
- Leading diagonal of array in A100461.at n=14A100462
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, -1), (0, 1, -1), (0, 1, 1), (1, -1, 0)}.at n=9A148828
- Number of 3 X n binary arrays without the pattern 0 1 diagonally, vertically, antidiagonally or horizontally.at n=46A188554
- Number of partitions of n where the difference between consecutive parts is at most 2.at n=47A224956
- Numbers k such that prime(k) + 1, ..., prime(k + 5) + 1 have the same number of prime divisors (with multiplicity).at n=4A255193
- a(n) = a(n - 1) + a(n - 2) + a(n - 3) for n>2, a(0)=5, a(1)=7, a(2)=9.at n=14A268410
- a(n) = Sum_{k=0..n} floor(sqrt(k))^4.at n=40A363498
- Integers k for which A000594(k)^2 > 4 k^11, where A000594 is Ramanujan's tau function.at n=42A364087