12618
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
- 4
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 27378
- Proper Divisor Sum (Aliquot Sum)
- 14760
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4200
- Möbius Function
- 0
- Radical
- 4206
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 94
- 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 distinct perforation patterns for deriving (v,b) = (n+2,n) punctured convolutional codes from (2,1).at n=8A007223
- Numbers k such that d(k) + d(k+1) + d(k+2) = 8, where d(k) = A001223.at n=44A064026
- Multiples of 18 containing a 18 in their decimal representation.at n=33A121038
- Value of A063882 at start of n-th generation of terms.at n=13A132176
- Ordered differences of central binomial coefficients.at n=33A205008
- Number of partitions of n such that (least part) <= (multiplicity of greatest part).at n=35A240179
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 462", based on the 5-celled von Neumann neighborhood.at n=33A272311
- Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 30", based on the 5-celled von Neumann neighborhood.at n=13A274476
- Triangle read by rows: T(n,k) = number of ways to insert n pairs of parentheses in k words.at n=46A275431
- Row 3 of array in A284731.at n=5A284733
- Integers m that divide the sum of values d*p < m, where d is a divisor of m, p is a prime, and d*p does not divide m.at n=14A350878
- Number of pairs of Dyck paths of semilength n such that the midpoint of the first is not below the midpoint of the second.at n=6A357652
- Number of 3 X 3 matrices with unit determinant and nonnegative integer entries whose sum is n.at n=18A361083
- Number of nondegenerate balanced Boolean functions of n variables.at n=4A378302
- Numbers k such that the powerful part of the sum of divisors of k (A387726) is greater than or equal to k, and sigma(k) is not itself a powerful number.at n=14A387729
- a(n) = Sum_{k=0..n} binomial(k+2,2) * binomial(k,3*n-3*k).at n=11A392313