13467
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 18228
- Proper Divisor Sum (Aliquot Sum)
- 4761
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8844
- Möbius Function
- 0
- Radical
- 201
- 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
- 89
- 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
- no
- Odd
- yes
Appears in sequences
- Number of numerical semigroups of genus n; conjecturally also the number of power sum bases for symmetric functions in n variables.at n=18A007323
- Self-convolution of composite numbers.at n=28A023648
- Number of partitions of n into parts not of the form 23k, 23k+8 or 23k-8. Also number of partitions with at most 7 parts of size 1 and differences between parts at distance 10 are greater than 1.at n=35A035996
- Numerators of continued fraction convergents to sqrt(521).at n=8A041996
- Composites c whose decimal expansion ends with its largest prime factor.at n=33A050693
- Prime(n)*prime(2*n)+prime(n)+prime(2*n).at n=20A072672
- 3p^2 where p runs through the primes.at n=18A079705
- Numbers k such that the numerator of Bernoulli(2k) is divisible by the square of 67, the third irregular prime.at n=14A093059
- a(n) = ceiling((9*(9/4)^n - 4) / 5).at n=11A108870
- Number of partitions that are "2-close" to being self-conjugate.at n=48A108961
- Numbers k whose digits can be divided into two contiguous parts, k = concatenate(x, y), such that k = |x^2 - y^2|.at n=6A113797
- Partial sums of primes that are not Chen primes (starting with 1).at n=38A118483
- Number of isomorphism classes of 6-regular loopless multigraphs of order n.at n=7A129422
- Numbers k which can be split into two numbers x and y such that x^3 + y^2 is a multiple of k.at n=33A162451
- Numbers k which are concatenations k=x//y such that x^2 + y^2 - x*y = k.at n=28A162556
- Numbers k which are concatenations k = x//y such that x^2 - y^2 is a multiple of k.at n=5A162701
- Triangle read by rows: T(n,k) is the number of permutations of n elements with transposition distance equal to k, n >= 1 and 0 <= k <= A065603(n).at n=27A164366
- Numbers of the form 20*k+7 which are three times a square.at n=13A192328
- G.f.: exp( Sum_{n>=1} A119616(n)*x^n/n ) where A119616(n) = (sigma(n)^2 - sigma(n,2))/2.at n=25A201825
- a(n) = (a(n-1) + a(n-3))/gcd(a(n-1), a(n-3)) with a(0) =2, a(1) = 3, a(2) = 5.at n=58A214331