6443 has 4 divisors (see below), whose sum is σ = 6840.
Its totient is φ = 6048.
The previous prime is 6427. The next prime is 6449. The reversal of 6443 is 3446.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3446 = 2 ⋅1723.
It is a cyclic number.
It is not a de Polignac number, because 6443 - 24 = 6427 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 379 = 6443 / (6 + 4 + 4 + 3).
It is a magnanimous number.
It is a d-powerful number, because it can be written as 64 + 45 + 46 + 33 .
It is a Duffinian number.
It is a plaindrome in base 12.
It is a nialpdrome in base 10.
It is a zygodrome in base 3.
It is not an unprimeable number, because it can be changed into a prime (6449) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173 + ... + 206.
It is an arithmetic number, because the mean of its divisors is an integer number (1710).
26443 is an apocalyptic number.
6443 is a deficient number, since it is larger than the sum of its proper divisors (397).
6443 is a wasteful number, since it uses less digits than its factorization.
6443 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 396.
The product of its digits is 288, while the sum is 17.
The square root of 6443 is about 80.2683000941.
The cubic root of 6443 is about 18.6078434566.
Adding to 6443 its reverse (3446), we get a palindrome (9889).
The spelling of 6443 in words is "six thousand, four hundred forty-three".