9138
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 18288
- Proper Divisor Sum (Aliquot Sum)
- 9150
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 3044
- Möbius Function
- -1
- Radical
- 9138
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 34
- 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
- Powers of cube root of 5 rounded to nearest integer.at n=17A017989
- Powers of cube root of 5 rounded up.at n=17A017990
- Triangular polyominoes (n-iamonds) without bilateral symmetry (holes are allowed).at n=12A030224
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 94.at n=23A031592
- Fourth column (r=3) of FS(3) staircase array A062745.at n=35A062748
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 85 ).at n=35A063358
- Number of compositions of n with first part 3 and no equal adjacent parts; this is column 3 of the array in A096568.at n=20A096571
- Numbers n such that n/6 and prime(n)+/-n are all primes.at n=16A105550
- Moebius transform of tetrahedral numbers.at n=36A117108
- Number of binary strings of length n with no substrings equal to 0001, 0110, or 0111.at n=25A164476
- Partial sums of A006567.at n=27A172463
- a(n) = (-1)^(n-3)*binomial(n,3) - 1.at n=36A216414
- Bernoulli denominators with 8 divisors in increasing order (without repetitions).at n=41A219742
- Number of length n+6 0..1 arrays with every seven consecutive terms having the maximum of some three terms equal to the minimum of the remaining four terms.at n=9A250366
- G.f. A(x) satisfies: 1/(1-x) = Product_{n>=1} A( x^n/(1+x)^n ).at n=15A268649
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 901", based on the 5-celled von Neumann neighborhood.at n=18A273744
- Solution of the complementary equation a(n) = 2*a(n-1) - a(n-2) + b(n-1) + n, where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.at n=28A294872
- Expansion of Product_{k>=1} (Product_{j=1..k} 1/(1 - x^(k*j))^(k*j)).at n=14A327068
- Irregular triangle: T(n,k) gives the number of k-polysticks on edges of the n-cube up to isometries of the n-cube, with 0 <= k <= A001787(n).at n=45A333333
- a(n) = floor(b(n)), where b(1) = 1 and b(n) = b(n-1) + Sum_{k=1..n-1} b(k)/(n-1).at n=34A376995