9050
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 16926
- Proper Divisor Sum (Aliquot Sum)
- 7876
- 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
- 3600
- Möbius Function
- 0
- Radical
- 1810
- 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
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite EUO = EU-1 Nan[AlnSi112-nO224] starting with a T7 atom.at n=12A019126
- a(n) = n*(29*n - 1)/2.at n=25A022286
- Otto Haxel's guess for magic numbers of nuclear shells.at n=30A033547
- Internal digits of n^2 include digits of n as subsequence.at n=33A046834
- a(n) = floor(C(n+6,6)/C(n+2,2)).at n=38A084626
- Slowest increasing sequence where the absolute difference between the last digit of a(n) and the first digit of a(n+1) equals 9.at n=17A101243
- Matrix square of triangle A104980.at n=40A104988
- Partial sums of primes that are not Chen primes (starting with 1).at n=31A118483
- The number of adjacency matrices generated with heuristics for different values of Wiener index.at n=6A121851
- Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, 0), (0, -1), (1, -1), (1, 0), (1, 1)}.at n=10A151456
- a(n) = (n^3 + 4*n^2 - n)/2.at n=24A162260
- a(n) = (2*n^3 + 5*n^2 + 5*n)/2.at n=19A162267
- If 0 <= n <= 3 then a(n) = n(n+1)(n+2)/3, if n >= 4 then a(n) = n(n^2+5)/3.at n=30A162626
- Expansion of (x^2)/((1-x)*(1-2*x-x^2+x^3)^2).at n=10A189427
- Triangle generated by the recurrence T(n+1,k+1) = T(n,k+1) + n * T(n,k) + delta(n,k) with the initial values T(n,0) = 1 and T(0,k) = delta(k,0), where delta(n,k) is the Kronecker delta.at n=40A191490
- Central coefficients of triangle A191490.at n=4A191492
- Number of meanders filling out an n X n grid, reduced for symmetry.at n=5A200000
- Triangle read by rows: number of meanders filling out an n X k grid.at n=20A200893
- a(n) = 13*n^2 - 16*n + 5.at n=27A202141
- Modular recursion: a(0)=a(1)=a(2)=a(3)=1, thereafter: a(n) equals a(n - 2) + a(n - 3) when n = 0 mod 5, a(n - 1) + a(n - 3) when n = 1 mod 5, a(n - 1) + a(n - 2) when n = 2 mod 5, a(n - 1) + a(n - 4) when n = 3 mod 5, and a(n - 1) + a(n - 2) + a(n - 3) otherwise.at n=27A206012