9028
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 16492
- Proper Divisor Sum (Aliquot Sum)
- 7464
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4320
- Möbius Function
- 0
- Radical
- 4514
- 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
- 39
- 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 loopless rooted planar maps with 3 faces and n vertices and no isthmuses. Also a(n)=T(4,n-3), array T as in A049600.at n=34A006416
- [ (4th elementary symmetric function of S(n))/(2nd elementary symmetric of S(n)) ], where S(n) = {3,4, ..., n+5}.at n=21A024194
- a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026615.at n=6A026957
- Number of basis partitions of n+36 with Durfee square size 6.at n=25A053801
- Number of ways to tile a 4 X n region with 1 X 1, 2 X 2, 3 X 3 and 4 X 4 tiles.at n=9A054856
- Indices of primes which remain prime if any one digit is deleted (leading zeros allowed).at n=43A084375
- Numbers k such that 5^k + 6 is prime.at n=17A089142
- Numbers k such that sigma(phi(k))-phi(sigma(k)) is nonzero and divisible by phi(k), that is A065395(k)/A000010(k) is a nonzero integer.at n=41A092587
- Numbers n such that (6^n-1)^2-2 is prime.at n=13A100901
- Number of distinct representations of 8n^3 as the sum of two primes.at n=50A116981
- a(n) = RMS( A141393(0) through A141393(n) ).at n=14A141394
- a(n) = 12*a(n-1) - 34*a(n-2), for n > 1, with a(0) = 1, a(1) = 14.at n=4A164598
- Numbers n with property that n^3+n^2+{3,5} are twin primes.at n=28A168254
- Numbers n such that 15*prime(n)+{-4,-2,2,4} are all primes.at n=27A176002
- Number of 2X4 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 2 zero-sum 4-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).at n=8A192699
- Number of tilings of a 9 X n rectangle using integer-sided square tiles.at n=4A219928
- Length of the maximal prefix of noncomposite numbers on row n of A249821.at n=62A250473
- The growth series for the affine Coxeter (or Weyl) group [3,3,5] (or H_4).at n=28A266783
- Number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 237", based on the 5-celled von Neumann neighborhood.at n=49A270980
- a(n) = number of n-digit binary numbers in which the first k and last k digits have a Hamming distance of 1 or less, for all k from 1 to n.at n=40A288793