6209
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 7104
- Proper Divisor Sum (Aliquot Sum)
- 895
- 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
- 5316
- Möbius Function
- 1
- Radical
- 6209
- 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
- 155
- 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
- Crystal ball sequence for diamond.at n=19A007904
- a(n) = n!*L_{n}(1), where L_{n}(x) is the n-th Laguerre polynomial.at n=8A009940
- Powers of fifth root of 8 rounded up.at n=21A018137
- Numbers k such that Fib(k) == -13 (mod k).at n=23A023167
- a(n) = least m such that if r and s in {1/1, 1/4, 1/7, ..., 1/(3n-2)} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=35A024836
- Number of days in n years (n=4 is the first leap year).at n=16A033171
- Number of days in n years (n=3 is the first leap year).at n=16A033172
- Number of days in n years (n=2 is the first leap year).at n=16A033173
- Composite numbers whose prime factors contain no digits other than 7 and 8.at n=5A036323
- Numerators of continued fraction convergents to sqrt(834).at n=7A042610
- Squarefree nonprimes with property that the concatenation of the prime factors is a palindrome.at n=45A046448
- Semiprimes whose prime factors, when concatenated, yield a palindrome.at n=39A046451
- Positions of 4-digit terms in the continued fraction for Pi (3 is at position 0).at n=5A048959
- Revert transform of 2*x*(1 - x + x^4)-x/(1+x).at n=8A049174
- Denominators of continued fraction for left factorial.at n=16A056920
- Numbers k such that binomial(2k,k)+1 is prime.at n=28A066699
- Least number requiring the base n to produce a prime by base reversal.at n=36A075244
- Row sums of A103441. Number of two-colored bracelets of n beads with different sets of distances among the white beads.at n=16A103442
- Smaller of two consecutive semiprimes with the same digital root.at n=40A118699
- A106486-encodings of combinatorial games with value 1.at n=26A125992