11988
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 30
- Divisor Sum
- 32186
- Proper Divisor Sum (Aliquot Sum)
- 20198
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3888
- Möbius Function
- 0
- Radical
- 222
- 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
- 50
- 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
- sigma_3(n): sum of cubes of divisors of n.at n=21A001158
- Number of paraffins.at n=35A005997
- Sum of cubes of unitary divisors of n.at n=21A034677
- Dirichlet inverse of sigma_3 function (A001158).at n=21A053825
- Least k for which the integers floor(2k/(m*(m+1))) for m=1,2,...,n are distinct.at n=40A054064
- a(n) = n^3*Product_{distinct primes p dividing n} (1+1/p^3).at n=21A065959
- Engel expansion of sinh(1/3).at n=18A068380
- a(0)=1, a(n) = sigma_3(2n).at n=11A091986
- a(n) = sigma_3(3n+1).at n=7A092342
- a(n) = n^2*(2*n+1).at n=18A099721
- a(n) = n*(20 + 15*n + n^2)/6.at n=36A101853
- a(n) = phi(Padovan(n+4)).at n=36A107797
- Number of partitions of n such that even parts occur at most once and odd parts occur at most twice.at n=51A118246
- Expansion of g.f.: -x*(1 - 2*x + 6*x^2 - 2*x^3 + x^4)/((1-x)^3*(1+x)^4).at n=35A122576
- a(n) = n*floor(n/2)^2.at n=37A122656
- Number of 5-way intersections in the interior of a regular 6n-gon.at n=36A137939
- Antidiagonal sums of the triangle A120070.at n=34A143785
- a(n) = 9*n*(n+1).at n=36A163758
- a(n) = Sum_{d|n} A007955(d) * A007955(n/d), where A007955(m) = product of divisors of m.at n=17A174936
- The sums of pairs of adjacent terms are the odd palindromic primes in ascending order.at n=36A181882