6549
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 9120
- Proper Divisor Sum (Aliquot Sum)
- 2571
- 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
- -1
- Radical
- 6549
- 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
- 44
- 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
- a(n) = floor(n*(n-1)*(n-2)/13).at n=45A011895
- Product of n with 666 is palindromic.at n=43A030094
- 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 52.at n=39A031550
- Rounded difference between 10^n/(log(10^n) - A) and pi(10^n), where A is Legendre's constant and pi is the prime counting function.at n=8A058290
- Numbers k such that numerator of Bernoulli(2*k) is divisible by 37 and 59, the first two irregular primes.at n=26A092231
- On the Z^2 lattice, number of paths of length 2*p+1 that start at (1,0) and pass through the origin.at n=3A108740
- First differences of [0, A047970].at n=8A112532
- Indices n corresponding to the terms in A153353.at n=5A125085
- Numbers k such that the number of digits d in k^2 is not prime and for each factor f of d the sum of the d/f digit groupings in k^2 of size f is a square.at n=16A153745
- Numbers k such that there are 8 digits in k^2 and for each factor f of 8 (1,2,4) the sum of digit groupings of size f is a square.at n=6A153746
- Number of n X n 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value.at n=2A164759
- Number of nX4 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value.at n=2A164761
- For any number n take the polynomial formed by the product of the terms (x-pi), where pi's are the prime factors of n. Then calculate the area between the minimum and the maximum value of the prime factors. This sequence lists the numbers for which the area is a positive integer.at n=42A203612
- Triangle T(n,k), 0<=k<=n, read by rows, given by (0, 1, 1, 3, 3, 6, 6, 10, 10, 15, ...) DELTA (1, 0, 2, 0, 3, 0, 4, 0, 5, ...) where DELTA is the operator defined in A084938.at n=42A211183
- Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=2A252098
- Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=0A252100
- T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=3A252105
- T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=5A252105
- Number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 411", based on the 5-celled von Neumann neighborhood.at n=45A271889
- First 4-digit number to appear n times in the decimal expansion of Pi.at n=4A276686