16740
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 48
- Divisor Sum
- 53760
- Proper Divisor Sum (Aliquot Sum)
- 37020
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4320
- Möbius Function
- 0
- Radical
- 930
- Omega Function (Ω)
- 7
- 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
- Shifts left 2 places under "DIK" (bracelet, indistinct, unlabeled) transform.at n=16A032291
- Numbers k such that sigma (x) = k has exactly 11 solutions.at n=19A060678
- Triangle read by rows: T[n,k] = number of n X n binary matrices with k=0...n^2 ones, distinct up to cyclic shifts of rows and columns; reflection through any vertical or horizontal axis; and reflection through the main diagonal. Also, quasi-n-ominoes on a torus divided into a k X k grid.at n=44A093466
- Triangle read by rows: T[n,k] = number of n X n binary matrices with k=0...n^2 ones, distinct up to cyclic shifts of rows and columns; reflection through any vertical or horizontal axis; and reflection through the main diagonal. Also, quasi-n-ominoes on a torus divided into a k X k grid.at n=49A093466
- a(n) = Sum_{k=0..n} (k-1)^k.at n=5A095937
- Structured hexagonal anti-prism numbers.at n=19A100183
- a(n) = 2*a(n-1) - 3*a(n-2) + 2*a(n-3) with a(0) = 3, a(1) = 4, a(2) = 0.at n=26A105576
- Triangle read by rows: T(n,k) = number of simple graphs on n labeled nodes with k edges that are node-disjoint unions of undirected cycle subgraphs.at n=52A144161
- a(n) = binomial(n+1,2)*6^2.at n=30A162940
- Number of nX4 1..3 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nonincreasing order.at n=5A166835
- Numbers such that each digit from 0 to 9 appears at least 7 times in the digits of their divisors.at n=12A175507
- Numbers k such that sopfr(k + omega(k)) = sopfr(k), where sopfr(i) = A001414(i) and omega(i) = A001221(i).at n=17A187878
- Number of arrays of 4 integers in -n..n with sum zero and adjacent elements differing in absolute value.at n=14A202964
- Number of n X 4 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.at n=27A208375
- Triangle read by rows, S_4(n, k) where S_m(n, k) are the Stirling-Frobenius subset numbers of order m; n >= 0, k >= 0.at n=24A225469
- a(n) = Sum_{i=0..n} digsum_9(i)^3, where digsum_9(i) = A053830(i).at n=44A231686
- a(n) = Sum_{i=0..n} digsum(i)^3, where digsum(i) = A007953(i).at n=44A231688
- Exponential (2,4)-perfect numbers: numbers m such that esigma(esigma(m)) = 4m, where esigma(m) is the sum of exponential divisors of m (A051377).at n=8A328133
- a(n) = A332214(n) - n, where A332214 is the Mersenne-prime fixing variant of permutation A163511.at n=67A366372
- Table read by antidiagonals: Place k points in general position on each side of a regular n-gon and join every pair of the n*(k+1) boundary points by a chord; T(n,k) (n >= 3, k >= 0) gives number of vertices in the resulting planar graph.at n=42A367183