6683
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6888
- Proper Divisor Sum (Aliquot Sum)
- 205
- 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
- 6480
- Möbius Function
- 1
- Radical
- 6683
- Omega Function (Ω)
- 2
- 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
- 93
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Spiral sieve using Fibonacci numbers.at n=18A005622
- a(n) = n*(4*n-1).at n=41A033991
- Numerators of continued fraction convergents to sqrt(275).at n=7A041516
- Numbers whose base-9 representation has exactly 5 runs.at n=28A043634
- a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 4.at n=12A049947
- In base 2: smallest integer which requires n 'Reverse and Add' steps to reach a palindrome.at n=44A066058
- a(n) is the smallest number such that gcd(a(n), sigma(a(n))) = n.at n=40A074391
- a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) + a(n-4).at n=10A093406
- a(n) = Sum_{k=0..n} C(n,4k)*2^k.at n=13A097081
- Numbers n such that n^2+n+41 (Euler's "prime generating polynomial") is not squarefree.at n=41A097823
- Numbers n such that 3*10^n + 4*R_n + 3 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=7A102969
- Expansion of 1 / Product_{n>=0} (1 - q^(5n+1))*(1 - q^(5n+2))*(1 - q^(5n+4)).at n=44A107235
- Expansion of solution of functional equation.at n=9A112808
- Semiprimes k=p*q such that the polynomial (1+x)^k (mod k) has p+q nonzero terms.at n=31A116926
- Number of B-trees of order infinity with n leaves, where a(n) = Sum_{k=1..floor(n/2)} a(k)*C(n-k-1,n-2*k) for n >= 2, with a(0)=0, a(1)=1.at n=18A119262
- Sum of the quadratic nonresidues of prime(n).at n=37A125615
- Records in A018892.at n=42A126097
- a(n) = least k such that the remainder when 19^k is divided by k is n.at n=11A128159
- Composite numbers generated by the Euler polynomial x^2 + x + 41.at n=7A145292
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, 0), (0, 0, 1), (0, 1, -1), (1, 0, -1)}.at n=9A148565