15747
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
- 8
- Divisor Sum
- 21840
- Proper Divisor Sum (Aliquot Sum)
- 6093
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10080
- Möbius Function
- -1
- Radical
- 15747
- Omega Function (Ω)
- 3
- 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
- 146
- Smith Number
- yes
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = floor( n^e ), e = 2.718281828...at n=34A061293
- Number of indecomposable set partitions of [1..n] without singletons.at n=10A098742
- Triangle T(n,k) defined by: T(0,0)=1, T(n,k)=0 if k < 0 or k > n, T(n,k) = T(n-1,k-1) + k*T(n-1,k) + Sum_{j>=1} T(n-1,k+j).at n=46A116155
- Sum of n!!, with n>=0.at n=11A129981
- Weight distribution of a certain binary linear code of length 56 defined by AES (or Rijndael) S-box.at n=9A131620
- Numerators b(n) of Pythagorean approximations b(n)/a(n) to 5/4.at n=5A195566
- Triangle read by rows, T(n,k) for 0<=k<=n, generalizing A098742.at n=36A216916
- Number of n element 0..1 arrays with each element the minimum of 7 adjacent elements of a random 0..1 array of n+6 elements.at n=27A217838
- Index of the first superabundant number k having abundance >= n.at n=14A240074
- a(n) = smallest m such that A031131(m) = 2*n.at n=41A261525
- p-INVERT of (1,0,0,1,0,0,0,0,0,0,...), where p(S) = 1 - S^2.at n=33A292402
- Numbers X such that X^2 + Y^2 = 3^(2*k) + 1 and X > Y > 0 and k is the ternary digit length of X-1.at n=17A369768
- Expansion of (1 - x - x^4)/((1 - x - x^4)^2 - 4*x^5).at n=17A375282