7644
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
- 4
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 22344
- Proper Divisor Sum (Aliquot Sum)
- 14700
- 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
- 2016
- Möbius Function
- 0
- Radical
- 546
- Omega Function (Ω)
- 6
- 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
- 31
- 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
- a(n) = T(3n,n), where T is the array defined in A025177.at n=5A025185
- a(n) = T(3n,n), where T is the array in A026148.at n=5A026158
- Number of diagonal dissections of an n-gon into 4 regions.at n=7A033276
- Number of diagonal dissections of a convex (n+9)-gon into n+1 regions.at n=3A033281
- Triangle read by rows: T(n, k) is the number of diagonal dissections of a convex n-gon into k+1 regions.at n=48A033282
- Theta series of A2[hole]^4.at n=27A033690
- Number of odd split numbers (A036382) in the interval [2^(n-1), 2^n].at n=15A036384
- Numbers k such that phi(k) is equal to A008473(k).at n=8A039779
- Triangle of numbers of Dyck paths.at n=51A039797
- Triangle read by rows: numbers of Dyck paths.at n=48A039798
- Sum of divisors of those numbers n such that n and n+1 have the same sum of divisors.at n=8A053215
- Series for 2nd parallel moment of square lattice bond percolation near a wall (eventually goes negative).at n=8A056598
- Number of orientable necklaces with 2n beads and two colors which when turned over produce their own color complement.at n=15A059078
- Number of rods required to make a 3-D cube of side length n.at n=13A059986
- Numbers k such that sigma(x) = k has exactly 10 solutions.at n=11A060666
- Degrees of irreducible representations of alternating group A_14.at n=30A060717
- Growth series for Heisenberg group.at n=17A063810
- Binary string self-substitutions: a(n) is obtained by substituting the binary expansion of n for each 1-bit in the binary expansion of n.at n=14A065159
- Number of regions in regular n-gon which are quadrilaterals (4-gons) when all its diagonals are drawn.at n=24A067151
- Numbers k such that sigma(k+1) = 5*phi(k).at n=3A067263