16440
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 32
- Divisor Sum
- 49680
- Proper Divisor Sum (Aliquot Sum)
- 33240
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4352
- Möbius Function
- 0
- Radical
- 4110
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 4
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
- yes
- 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
- Number of ways of writing n as a sum of 6 squares.at n=37A000141
- Number of ways of getting a straight flush, 4 of a kind, full house, flush, straight, 3 of a kind, 2 pair, a pair, nothing in a 3-card poker hand.at n=8A002834
- Dirichlet convolution of b_n = 2^(n-1) with phi(n).at n=14A034738
- Number of primitive (aperiodic) reversible string structures with n beads using a maximum of two different colors.at n=15A056331
- Number of primitive (aperiodic) reversible string structures with n beads using exactly two different colors.at n=15A056336
- Triangle T(n,k) giving number of fixed 5 X k polyominoes with n cells (n >= 5, 1<=k<=n-4).at n=48A059681
- a(0)=1; a(n) = sigma_1(n) + sigma_3(n).at n=24A092345
- Numbers n such that 4*10^n + 5*R_n - 2 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=17A102991
- 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, 1), (0, 1, -1), (0, 1, 0), (1, 0, 0), (1, 1, -1)}.at n=9A149836
- Expansion of e.g.f. 1/( cos(log(1-x)) + sin(log(1-x)) ).at n=6A184942
- Number of 4-step left-handed knight's tours (moves only out two, left one) on an n X n board summed over all starting positions.at n=24A187174
- Number of 5-step S, E, and NW-moving king's tours on an n X n board summed over all starting positions.at n=19A187510
- Related to number of Hadamard matrices of order 4n.at n=4A199006
- Related to number of cocyclic Hadamard matrices of order 4n.at n=4A199007
- Number of nX5 0..1 arrays with exactly floor(nX5/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..1 order.at n=5A222453
- Number of nX6 0..1 arrays with exactly floor(nX6/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..1 order.at n=4A222454
- T(n,k) = Number of n X k 0..1 arrays with exactly floor(n X k/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..1 order.at n=49A222456
- T(n,k) = Number of n X k 0..1 arrays with exactly floor(n X k/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..1 order.at n=50A222456
- Number of (not necessarily maximal) cliques in the n-sun graph.at n=13A295904
- a(n) = A306898(n)/2.at n=14A306905