16654
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 27288
- Proper Divisor Sum (Aliquot Sum)
- 10634
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7560
- Möbius Function
- -1
- Radical
- 16654
- Omega Function (Ω)
- 3
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 66
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Base 3 digits are, in order, the first n terms of the periodic sequence with initial period 2,1,1.at n=8A037552
- Number of n-element T_0-antichains on a labeled set.at n=3A059079
- Members of A000124 which are multiples of 11.at n=33A083511
- a(n)*n = A112902(n).at n=3A112903
- For each permutation p of {1,2,...,n} define minabsjump(p) = min(|p(i) - i|, 1<=i<=n); a(n) is the sum of minabsjumps of all p.at n=7A129118
- Years >= 1801 in which Christmas falls in Sukkot.at n=28A222419
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 598", based on the 5-celled von Neumann neighborhood.at n=41A273151
- Numbers k such that k | A047842(k).at n=10A278439
- Number of permutations of [n] having exactly ten (possibly overlapping) doubledescents.at n=2A279299
- Triangle T(n,k), n >= 2, 0 <= k <= floor(n^2/2)-2*n+2, read by rows, where T(n,k) is the number of 2*(k+2*n-2)-cycles in the n X n grid graph which pass through four corners ((0,0), (0,n-1), (n-1,n-1), (n-1,0)).at n=16A333668
- Greatest integer whose square root is less than or equal to Sum_{j=0..n} sqrt(j).at n=33A338277
- E.g.f. A(x) satisfies A(x) = 1 + 2 * (1 - exp(-x)) * A(2 * (1 - exp(-x))).at n=4A355132
- Expansion of g.f. A(x) satisfying A(x) = x + x^2 + (A(x)^3 + 2*A(x^3))/3.at n=17A375438
- a(n) = Sum_{d|n} d^d * binomial(n/d-1,d-1).at n=29A376018