6291
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 9360
- Proper Divisor Sum (Aliquot Sum)
- 3069
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4176
- Möbius Function
- 0
- Radical
- 699
- Omega Function (Ω)
- 4
- 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
- 62
- 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
- a(n) = Catalan(n) + Catalan(n+1) - 1.at n=8A000778
- Number of black-rooted red-black trees with n internal nodes.at n=14A001137
- Pentagonal numbers written backwards.at n=36A004163
- Fibonacci sequence beginning 0, 27.at n=13A022361
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 79.at n=7A031577
- Number of n X n invertible matrices A over GF(3) such that A-I is invertible.at n=2A051680
- a(1)=1, a(n)=a(n-a(1))+a(n-a(2))+a(n-a(3))+....a(n-a(n-1)) for n>1, with convention that a(i)=0 for i<=0.at n=11A052109
- First (leftmost) digit - second digit + third digit - fourth digit .... = 12.at n=46A061881
- Composites for which the row of the prime-composite array (A063173) includes the leftmost element of both a zero-only antidiagonal and a zero-only diagonal(A067681).at n=38A063176
- Non-balanced numbers in A015765.at n=27A074868
- Diagonal of triangular spiral in A051682.at n=37A081267
- Diagonal in array of n-gonal numbers A081422.at n=17A081438
- Numbers k such that the k-th prime is of the form 2*j^2 + 1.at n=27A090612
- Add/multiply sequence, see example.at n=33A093361
- Frequency of the hexadecimal 5 in the first 10^n hexadecimal digits of Pi.at n=4A099338
- Numbers n such that (n + prime(n)), (n+1 + prime(n+1)) and (n+2 + prime(n+2)) are divisible by 5.at n=40A107581
- Numbers n such that (n + prime(n)), (n+1 + prime(n+1)), (n+2 + prime(n+2)) and (n+3 + prime(n+3)) are divisible by 5.at n=0A107582
- Sum of non-Fibonacci numbers between successive Fibonacci numbers: a(n) = Sum_{k=F(n)+1..F(n+1)-1} k.at n=11A109454
- Concerning the popular MMORPG "Runescape" by JAGeX corporation, this sequence gives the number of experience points needed for a given level in a skill.at n=22A111078
- a(1) = 3, a(2) = 4. a(n) = (largest composite which occurs earlier in sequence) + (largest prime which occurs earlier in sequence).at n=23A120365