15996
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 30
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 39424
- Proper Divisor Sum (Aliquot Sum)
- 23428
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5040
- Möbius Function
- 0
- Radical
- 7998
- Omega Function (Ω)
- 5
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 190
- 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
- Pisot sequence T(7,10), a(n) = floor(a(n-1)^2/a(n-2)).at n=38A020752
- Theta series of A2[hole]^4.at n=35A033690
- Row sums of triangle A049029.at n=4A049120
- Low-temperature susceptibility expansion for honeycomb net (Potts model, q=3).at n=5A057391
- a(n) is the number of nonsymmetric patterns (no reflective, nor rotational symmetry) which may be formed by an equilateral triangular arrangement of closely packed black and white cells satisfying the local matching rule of Pascal's triangle modulo 2, where n is the number of cells in each edge of the arrangement. The matching rule is such that any elementary top-down triangle of three neighboring cells in the arrangement contains either one or three white cells.at n=13A060551
- Difference between A007678(2n)/(2n) and (n-1)^2.at n=38A085611
- G.f.: Product((1+x^i)/(1-x^i),i=1..n-1)/(1-x^n), with n = 8.at n=25A091779
- Pierce expansion of 1/e^2.at n=11A091832
- Convolution triangle, read by rows, where diagonals are successive self-convolutions of A118346.at n=60A118349
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, -1), (0, 1, 1), (1, 0, -1), (1, 0, 0)}.at n=8A150017
- Numerators b(n) of Pythagorean approximations b(n)/a(n) to 5/4.at n=6A195566
- Denominators a(n) of Pythagorean approximations b(n)/a(n) to 4/5.at n=3A195580
- Number of compositions of n such that the first part is 1 and the second differences of the parts are in {-1,0,1}.at n=28A239551
- Number of ways to choose three distinct points from a 5 X n grid so that they form an isosceles triangle.at n=34A271915
- Expansion of e.g.f. Product_{k>=1} 1 / (1 - x^k/k)^2.at n=6A371313