16677
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 25740
- Proper Divisor Sum (Aliquot Sum)
- 9063
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10368
- Möbius Function
- 0
- Radical
- 5559
- Omega Function (Ω)
- 4
- 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
- 159
- 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
- no
- Odd
- yes
Appears in sequences
- Number of non-stereoisomeric paraffins with n carbon atoms.at n=21A000627
- Number of loopless multigraphs with 8 nodes and n edges.at n=10A014398
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2), t = A000045 (Fibonacci numbers).at n=17A023860
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t = (F(2), F(3), F(4), ...), F(n) = Fibonacci(n).at n=16A023864
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = (Fibonacci numbers).at n=16A024857
- Numerators of continued fraction convergents to sqrt(474).at n=10A041904
- Numbers whose base-4 representation contains exactly three 0's and four 1's.at n=32A045032
- Square spiral of sums of selected preceding terms, starting at 1 (a spiral Fibonacci-like sequence).at n=18A094767
- The number of n-almost primes less than or equal to 8^n, starting with a(0)=1.at n=6A116428
- a(n) = Sum_{k=0..n} lcm(1..2n+2)/lcm(1..2k+2).at n=5A120106
- Beastly fax numbers: numbers containing the fax number of the Beast (667, one more than its regular number) in their decimal expansion.at n=34A138563
- Averages of four consecutive cubes.at n=25A173965
- 1/9 the number of (n+1) X 5 0..2 arrays with all 2 X 2 subblocks having the same four values.at n=12A184043
- The number of P-positions in the game of Nim with up to 4 piles, allowing for piles of zero, such that the number of objects in each pile does not exceed n.at n=26A241522
- Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock sum of the two medians of the central row and column minus the sum of the minimums of the diagonal and antidiagonal nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=1A257147
- Number of (n+2)X(2+2) 0..1 arrays with every 3X3 subblock sum of the two medians of the central row and column minus the sum of the minimums of the diagonal and antidiagonal nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=1A257148
- T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 3X3 subblock sum of the two medians of the central row and column minus the sum of the minimums of the diagonal and antidiagonal nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=4A257154
- Number of (2+2)X(n+2) 0..1 arrays with every 3X3 subblock sum of the two medians of the central row and column minus the sum of the minimums of the diagonal and antidiagonal nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=1A257155
- Integers k such that k = a^2 + b^2 = c^2 + d^2 and a + b = 3(c - d), where a, b, c and d are distinct positive integers.at n=40A369498
- Numbers k such that k - A067666(k) is a square.at n=36A386304