13428
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 34034
- Proper Divisor Sum (Aliquot Sum)
- 20606
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4464
- Möbius Function
- 0
- Radical
- 2238
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 89
- 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
- Numbers that are divisible by 6 (and 18) and are differences between two cubes in at least one way.at n=40A038852
- Expansion of (1+x*C^4)*C^3, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.at n=7A071264
- Number of planar partitions of n with exactly 5 rows.at n=15A091359
- Number of consecutive runs of just 1 odd nonprime congruent to 3 mod 4 below 10^n.at n=4A093184
- Ulam's spiral (NNW spoke).at n=29A143860
- Let p*q = A006881(n) be the n-th number that is the product of two distinct primes, with p = prime(i), q=prime(j); a(n) = p^j - q^i.at n=18A176885
- Number of ways to arrange 3 indistinguishable points on an n X n X n triangular grid so that no three points are collinear at any angle.at n=9A194131
- T(n,k) = number of ways to arrange k indistinguishable points on an n X n X n triangular grid so that no three points are collinear at any angle.at n=63A194136
- The location of records in A210700.at n=25A210701
- Numbers k such that k^8192 + (k+1)^8192 is prime.at n=2A274237
- a(n) = n*Sum_{i=0..n-1} binomial(n,i)*binomial(i-1,n-i-1)/(n-i).at n=10A279136
- Expansion of Product_{k>=1} ((1 + x^(2*k-1))/(1 - x^(2*k)))^k.at n=24A295832
- Number of n X 4 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0 or 2 neighboring 1s.at n=4A297334
- T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0 or 2 neighboring 1s.at n=32A297338
- Number of 5Xn 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0 or 2 neighboring 1s.at n=3A297342
- Least k such that A298475(k) = n.at n=5A298476
- Least k such that there are exactly A003586(n) ways to choose a binary index of each binary index of k.at n=35A368111
- Sorted positions of first appearances in A368109 (number of ways to choose a binary index of each binary index).at n=31A368112