13004
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 22764
- Proper Divisor Sum (Aliquot Sum)
- 9760
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6500
- Möbius Function
- 0
- Radical
- 6502
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 2
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
- 138
- 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
- Powers of cube root of 2 rounded to nearest integer.at n=41A017980
- Powers of cube root of 2 rounded up.at n=41A017981
- Number of partitions of n into parts not of the form 21k, 21k+8 or 21k-8. Also number of partitions with at most 7 parts of size 1 and differences between parts at distance 9 are greater than 1.at n=35A035986
- Numbers whose base-5 representation contains exactly three 0's and three 4's.at n=3A045217
- Period of the continued fraction for sqrt(2^n-1).at n=29A059866
- Numbers whose set of base 5 digits is {0,4}.at n=41A097251
- Number of parallelograms on an n X n grid.at n=7A189416
- a(n) = 4*(5*n^2 - 5*n + 1).at n=25A193448
- Number of (w,x,y,z) with all terms in {1,...,n} and |w-x|=2|x-y|-|y-z|.at n=26A212577
- Number of conjugacy classes in Chevalley group G_2(q) as q runs through the prime powers.at n=39A225929
- Triangle read by rows: T(n,k) gives the number of ballot sequences of length n having largest descent k, n>=0, 0<=k<=n.at n=68A238128
- Triangle read by rows: T(n,k) gives the number of ballot sequences of length n having largest ascent k, n>=0, 0<=k<=n.at n=68A238129
- Number of n X 3 0..2 arrays with no element equal to the sum of elements to its left or one plus the sum of elements above it, modulo 3.at n=9A239025
- Number of ballot sequences of length n having largest descent 2.at n=7A244198
- Numbers whose k digits can be permuted into a new k-digit number according to rules explained in the Comments section.at n=6A330418
- Triangle of number of 312-avoiding reduced valid hook configurations with n hooks that are on permutations with 2n + k points, for n=1 and 1<=k<=n.at n=12A338368
- a(n) is the least k such that, if p is the greatest prime less than k, there is a prime between n*p and n*k, but for 1 < j < n there is no prime between j*p and j*k.at n=10A368208