7728
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 40
- Divisor Sum
- 23808
- Proper Divisor Sum (Aliquot Sum)
- 16080
- 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
- 2112
- Möbius Function
- 0
- Radical
- 966
- 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
- 26
- 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) = floor(Fibonacci(n)/6).at n=24A004699
- a(n) = round(n*phi^12), where phi is the golden ratio, A001622.at n=24A004947
- a(n) = ceiling(n*phi^12), where phi is the golden ratio, A001622.at n=24A004967
- Quadrinomial coefficients.at n=3A005724
- a(n) = floor(phi*a(n-2)) + a(n-1) where phi is the golden ratio.at n=15A005834
- Number of partitions of n with at least 1 odd and 1 even part.at n=32A006477
- Second (lower) diagonal of partition triangle A047812.at n=13A007045
- Expansion of e.g.f. arcsin(tanh(x) * log(x+1)).at n=8A012651
- E.g.f.: sinh(tanh(x)*log(x+1))=2/2!*x^2-3/3!*x^3-10/5!*x^5+280/6!*x^6...at n=8A012654
- a(n) = (d(n)-r(n))/5, where d = A026049 and r is the periodic sequence with fundamental period (4,1,4,0,1).at n=44A026051
- Number of partitions of n into parts 4k and 4k+2 with at least one part of each type.at n=64A035622
- Number of partitions of n into parts not of the form 17k, 17k+7 or 17k-7. Also number of partitions with at most 6 parts of size 1 and differences between parts at distance 7 are greater than 1.at n=33A035968
- Denominators of continued fraction convergents to sqrt(45).at n=11A041077
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 2, and a(3) = 3.at n=29A050051
- Number of asymmetric mobiles (circular rooted trees) with n nodes and 3 leaves.at n=22A055364
- Numbers k such that sigma(x) = k has exactly 7 solutions.at n=30A060663
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 73 ).at n=35A063346
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 87 ).at n=37A063360
- Numbers k such that the period of the continued fraction for sqrt(5)*k is 2.at n=29A065030
- Multiples of 24 whose digits also sum to 24.at n=27A066270