9520
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 40
- Divisor Sum
- 26784
- Proper Divisor Sum (Aliquot Sum)
- 17264
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3072
- Möbius Function
- 0
- Radical
- 1190
- Omega Function (Ω)
- 7
- Little Omega Function (ω)
- 4
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
- 78
- 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
- 9-gonal (or enneagonal) pyramidal numbers: a(n) = n*(n+1)*(7*n-4)/6.at n=20A007584
- a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ... + a(n-3)*a(3) for n >= 4, with initial terms 0, 1, 2, 0.at n=17A025251
- Number of triangles a queen can make (starting anywhere) on an n X n board.at n=17A030117
- Numbers whose set of base-13 digits is {1,4}.at n=29A032825
- Numbers whose set of base-13 digits is {3,4}.at n=29A032837
- Number of diagonal dissections of an n-gon into 3 regions.at n=16A033275
- a(n) = n*(n+1)*(n+2)*(n+3)/6.at n=14A033488
- Four times pentagonal numbers: a(n) = 2*n*(3*n-1).at n=40A033579
- Total number of possible knight moves on an (n+2) X (n+2) chessboard, if the knight is placed anywhere.at n=34A035008
- 1 / min{1/n - 1/a - 1/b > 0}, where a and b are integers.at n=13A045470
- a(n) in base 13 is a repdigit.at n=40A048337
- Triangle read by rows, the Bell transform of n!*binomial(2,n) (without column 0).at n=31A049404
- Binary encoding of quadratic residue set of n. L(1/n) is the most significant bit, L(n-1/n) is the least significant bit, i.e., the rows of A055088 interpreted as binary numbers.at n=14A055094
- Number of symmetric types of (3,2n)-hypergraphs under action of complementing group C(3,2).at n=30A055780
- Add column entries of the table with rows (1,2,0,0...), (0,3,4,5,0,0...), (0,0,6,7,8,9,0,0...), (0,0,0,10,11,12,13,14,0,0...), ...at n=38A064694
- T(n,k) = right- or upward-moving paths connecting opposite corners of an n X n chessboard, visiting the diagonal at k points between start and finish.at n=22A075435
- Generalized Stirling2 array (-1,2)S2. Irregular triangle a(n, m) for n >= 1 and 2 <= m <= 2*n.at n=20A091752
- Fifth column (m=6) of array A091752 ((-1,2)Stirling2).at n=2A091754
- Fourth column of (1,5)-Pascal triangle A096940.at n=33A096941
- Consider the smallest denominator q such that the Sylvester expansion of n/q has n terms. Here q has the form q = k*n+1 and we set a(n) = k.at n=18A098853