6443664 has 20 divisors (see below), whose sum is σ = 16646256. Its totient is φ = 2147872.

The previous prime is 6443639. The next prime is 6443677. The reversal of 6443664 is 4663446.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67074 + ... + 67169.

Almost surely, 2^6443664 is an apocalyptic number.

It is an amenable number.

6443664 is an abundant number, since it is smaller than the sum of its proper divisors (10202592).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6443664 is a wasteful number, since it uses less digits than its factorization.

6443664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134254 (or 134248 counting only the distinct ones).

The product of its digits is 41472, while the sum is 33.

The square root of 6443664 is about 2538.4373145697. The cubic root of 6443664 is about 186.0848266107.

The spelling of 6443664 in words is "six million, four hundred forty-three thousand, six hundred sixty-four".