6400443 has 16 divisors (see below), whose sum is σ = 9900800. Its totient is φ = 3602016.

The previous prime is 6400423. The next prime is 6400451. The reversal of 6400443 is 3440046.

It is not a de Polignac number, because 6400443 - 2⁵ = 6400411 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (6400403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 868 + ... + 3681.

It is an arithmetic number, because the mean of its divisors is an integer number (618800).

Almost surely, 2^6400443 is an apocalyptic number.

6400443 is a deficient number, since it is larger than the sum of its proper divisors (3500357).

6400443 is a wasteful number, since it uses less digits than its factorization.

6400443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4626.

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 6400443 is about 2529.9096821824. The cubic root of 6400443 is about 185.6678370454.

Adding to 6400443 its reverse (3440046), we get a palindrome (9840489).

The spelling of 6400443 in words is "six million, four hundred thousand, four hundred forty-three".