16956
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
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 44240
- Proper Divisor Sum (Aliquot Sum)
- 27284
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5616
- Möbius Function
- 0
- Radical
- 942
- Omega Function (Ω)
- 6
- 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
- 84
- 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
- a(n) = a(n-1) + a(n-2) + 1, with a(0) = 0, a(1) = 9.at n=17A022314
- Number of inner dual graphs of planar polyhexes with n hexagons.at n=11A108071
- Convolution of J(n)*n! and n! where J(n)=A001045(n), n-th Jacobsthal number.at n=6A110469
- Number of tilings of a 14 X n rectangle using 2n heptominoes of shape I.at n=22A250664
- Values of a^3 + b^3 such that the equation a^3 + b^3 = x^2 + y^2 + z^2 is not soluble where a, b > 0 and x, y, z >= 0.at n=39A272174
- Number of nX3 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-2) and new values introduced in order 0..2.at n=5A275347
- T(n,k)=Number of nXk 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-2) and new values introduced in order 0..2.at n=33A275352
- Number of 6Xn 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-2) and new values introduced in order 0..2.at n=2A275356
- a(n) = 6*n*(9*n-5).at n=18A277984
- Number of n X 3 0..1 arrays with every element equal to 0, 2, 3 or 6 king-move adjacent elements, with upper left element zero.at n=17A297981
- Numbers such that the product of their digits is equal to 10 times the sum of their prime factors, without multiplicity.at n=5A306313
- Number of integer partitions of n that have an even number of parts and cannot be partitioned into distinct pairs of not necessarily distinct parts.at n=45A338915
- Compositions (ordered partitions) of n into odd parts where the first part must be a maximal part.at n=26A368746
- Triangle read by rows: Coefficients of the polynomials S1(n, x) * EZ(n, x), where S1 denote the Stirling1 polynomials and EZ the Eulerian zig-zag polynomials A205497.at n=40A373429
- G.f.: Sum_{k>=0} x^(k*(k+1)) * Product_{j=1..k} 1/(1 - x^j)^3.at n=26A376708
- Number of normal multiset partitions of weight n into sets with distinct sizes.at n=9A382428