13145
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 17280
- Proper Divisor Sum (Aliquot Sum)
- 4135
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9520
- Möbius Function
- -1
- Radical
- 13145
- 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
- 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
- no
- Odd
- yes
Appears in sequences
- Least k such that first k terms of A022300 contain n more 2's than 1's.at n=22A025515
- Decimal part of cube root of a(n) starts with 6: first term of runs.at n=21A034132
- Number of asymmetric orthoplex n-ominoes in n-2 space.at n=10A036369
- Third unsigned column of triangle A051380.at n=5A051563
- Pseudo-random numbers: a (very weak) pseudo-random number generator from the second edition of the C book.at n=27A061364
- Triangle read by rows: T(n,k) is the number of Motzkin paths of length n and height k (n>=0, k>=0).at n=60A097862
- Numbers k such that 7*10^k + 9 is prime.at n=27A097954
- Absolute value of coefficient of x^3 in polynomial whose zeros are 5 consecutive integers starting with the n-th integer.at n=7A127694
- Numbers m such that product of factorials of digits of m equals sigma(m).at n=5A137603
- Index sequence to A089840: positions of bijections that preserve A127302 (the non-oriented form of binary trees) and whose behavior does not depend on whether there are internal or terminal nodes (leaves) in the neighborhood of any vertex.at n=40A153830
- Triangle read by rows: T(n,k) is the number of weighted lattice paths in L_n having k peaks.The members of L_n are paths of weight n that start at (0,0), end on the horizontal axis and whose steps are of the following four kinds: an (1,0)-step with weight 1, an (1,0)-step with weight 2, a (1,1)-step with weight 2, and a (1,-1)-step with weight 1. The weight of a path is the sum of the weights of its steps. A peak is a (1,1)-step followed by a (1,-1)-step.at n=36A182903
- Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 782", based on the 5-celled von Neumann neighborhood.at n=7A273535
- Partial sums of A301692.at n=88A301693
- A(n, k) is the smallest number x > A(n, k-1) such that every letter, with repetition, that occurs in the English name of A(n, k-1) also occurs in the English name of x, with A(n, 1) = n; square array, read by antidiagonals downwards.at n=45A303380
- Number of integer partitions of n whose product is divisible by the sum of primes of their parts.at n=47A330954
- Setwise difference A340150 \ A340076.at n=29A340151
- Triangle read by rows: T(n, k) = Sum_{i=0..n-k} Stirling1(i + m, m)*binomial(n+m+1, n-k-i)*(n + m - k)!/(i + m)!, for m = 2.at n=62A376634