15648
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 41328
- Proper Divisor Sum (Aliquot Sum)
- 25680
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5184
- Möbius Function
- 0
- Radical
- 978
- Omega Function (Ω)
- 7
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 53
- 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
- Coordination sequence for 4-dimensional cubic lattice (points on surface of 4-dimensional cross-polytope).at n=18A008412
- Coordination sequence for C_4 lattice.at n=9A019560
- Fibonacci sequence beginning 3, 14.at n=16A022125
- Positive numbers k such that k and 4*k are anagrams in base 9 (written in base 9).at n=15A023081
- Positive numbers k such that k and 5*k are anagrams in base 9 (written in base 9).at n=9A023082
- Square of the lower triangular normalized partition matrix.at n=38A027516
- Third column of A027516.at n=6A027530
- Variation on Ulam numbers: a(1) = 1; a(2) = 2; for n>2, a(n) is smallest (n odd) or largest (n even) new number that is the sum of two distinct earlier terms.at n=35A081025
- Expansion of phi(-q^9) / phi(-q) in powers of q where phi() is a Ramanujan theta function.at n=23A128770
- Number of nXnXn 0..6 triangular arrays with each element x equal to the number its neighbors equal to 5,0,2,2,3,2,1 for x=0,1,2,3,4,5,6.at n=5A197661
- Number of 0..n arrays x(0..9) of 10 elements with zero 5th differences.at n=36A200446
- Number of partitions p of n such that 2*(number of even numbers in p) <= (number of odd numbers in p).at n=42A241652
- Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 189", based on the 5-celled von Neumann neighborhood.at n=6A270678
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 390", based on the 5-celled von Neumann neighborhood.at n=45A271600
- G.f.: Sum_{n=-oo..+oo} (1 + x^n)^n / (1 - x^n)^n, ignoring the constant term.at n=50A292180
- Expansion of Product_{k>0} (1 + Sum_{m>0} x^(k*m!)).at n=45A304332