13935
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 22320
- Proper Divisor Sum (Aliquot Sum)
- 8385
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7424
- Möbius Function
- -1
- Radical
- 13935
- 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
- 151
- Smith Number
- no
- 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) = n*(31*n-1)/2.at n=30A022288
- Number of polyhexes of class PF2 (with one catafusene annealated to pyrene).at n=7A026106
- G.f. is G(x*(1-x)/(1-2*x)) where G(x) is g.f. for Catalan numbers A000108.at n=8A059278
- Expansion of (1-x)^(-1)/(1-2*x-2*x^2+2*x^3).at n=10A077847
- Expansion of (1-x)^(-1)/(1-x+x^2+2*x^3).at n=21A077873
- Indices of primes in the sequence defined by A(0) = 53, A(n) = 10*A(n-1) + 63 for n > 0.at n=19A101590
- "Ceiling of hypotenuses": a(n) = ceiling(sqrt(a(n-1)^2 + a(n-2)^2)), a(1)=1, a(2)=3.at n=35A104805
- Number of combinatorial types of neighborly 4-polytopes with n vertices.at n=6A133338
- Coefficient array of orthogonal polynomials P(n,x)=(x-n)*P(n-1,x)-(2n-3)*P(n-2,x), P(0,x)=1,P(1,x)=x-1.at n=45A178124
- Number of compositions of n that are both a reversed Lyndon word and a co-Lyndon word.at n=19A334269
- The longest length of consecutive primes which sums to prime = A342439(n) < 10^n.at n=8A342440