13026
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 28224
- Proper Divisor Sum (Aliquot Sum)
- 15198
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3984
- Möbius Function
- 1
- Radical
- 13026
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 45
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = ceiling(n*phi^13), where phi is the golden ratio, A001622.at n=25A004968
- Expansion of e.g.f.: sinh(tan(log(1+x))).at n=7A009601
- Number of partitions of n into an even number of parts.at n=38A027187
- Number of cycle types of conjugacy classes of all even permutations of n elements.at n=38A046682
- Truncated triangular pyramid numbers: a(n) = (n-7)*(n^2 + 10*n - 108)/6, n >= 8.at n=35A051941
- Number of non-associative non-commutative non-anti-associative non-anti-commutative closed binary operations on a set of order n.at n=2A079230
- Multiples of 13 containing a 13 in their decimal representation.at n=36A121033
- The Wiener index of the comb-shaped graph |_|_|...|_| with 2n (n>=1) nodes. The Wiener index of a connected graph is the sum of the distances between all unordered pairs of vertices in the graph.at n=25A192023
- Number of n-length words w over ternary alphabet such that for every prefix z of w we have #(z,a_i) = 0 or #(z,a_i) >= #(z,a_j) for all j>i and #(z,a_i) counts the occurrences of the i-th letter in z.at n=11A213291
- Numbers k such that at least one other integer m exists with the same smallest and same largest prime factors, and same multisets of decimal and binary digits as k.at n=29A214621
- Number of partitions of 2n of type EE (see Comments).at n=19A236913
- Number of partitions of n such that (greatest part) - (least part) = number of parts.at n=51A237832
- Numbers for which the harmonic mean of nontrivial divisors is an integer.at n=36A247078
- Numbers for which the harmonic mean of nontrivial divisors is an integer and which are not a square of prime numbers.at n=6A247079
- Triangle read by rows: T(n,k) = t(n-k, k), where t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1) and f(n) = 5*n + 3.at n=12A257623
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 369", based on the 5-celled von Neumann neighborhood.at n=26A268503
- a(n) = n^3/3 - 7*n/3 + 4.at n=34A270809
- Numbers n such that Bernoulli number B_{n} has denominator 3318.at n=10A272383
- Numbers k such that 7*10^k + 87 is prime.at n=20A274911
- Matula-Goebel numbers of transitive rooted identity trees (or transitive finitary sets).at n=16A290760