13180
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 27720
- Proper Divisor Sum (Aliquot Sum)
- 14540
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5264
- Möbius Function
- 0
- Radical
- 6590
- Omega Function (Ω)
- 4
- 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
- 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
- a(n) = T(n,0) + T(n,1) + ... + T(n,n), T given by A026519.at n=11A026531
- a(n) = Sum_{j=0..n} T(n, j), where T is given by A026552.at n=11A026564
- a(n) = T(n,m) + T(n,m+1) + ... + T(n,n), m=[ (n+1)/2 ], T given by A026780.at n=13A026902
- Number of partitions of n into parts 3k+1 and 3k+2 with at least one part of each type.at n=45A035620
- Interprimes which are of the form s*prime, s=20.at n=13A075295
- Sums of rows of the triangle in A116366.at n=44A116367
- Number of Fibonacci parts in the last section of the set of partitions of n.at n=31A144117
- Sums of two successive primes s such that s+-3 are primes.at n=25A179485
- Number of nondecreasing arrangements of n numbers in -3..3 with sum zero and sum of squares not greater than n*12/3.at n=26A183921
- Number of 8-element subsets of {1, 2, ..., n} having pairwise coprime elements.at n=17A186984
- Number of length 4+1 0..n arrays with the sum of the squares of adjacent differences multiplied by some arrangement of +-1 equal to zero.at n=10A250279
- G.f.: Sum_{n=-oo..+oo} x^n * (1 + x^n)^n, an even function.at n=45A260361
- Expansion of phi(-x^6) / f(-x) in powers of x where phi(), f() are Ramanujan theta functions.at n=40A271661
- Triangle T(m,k) read by rows, where T(m,k) is the number of ways in which 1<=k<=m positions can be picked in an m X m square grid such that the picked positions have a point symmetry or a line symmetry.at n=24A292153
- a(n) = n^4 + 3*n^3 + 2*n^2 - 2*n.at n=10A330651
- Number of integer partitions of 2n with exactly n distinct sums of nonempty submultisets.at n=35A365660