638463764 has 24 divisors (see below), whose sum is σ = 1245303360. Its totient is φ = 284639616.

The previous prime is 638463751. The next prime is 638463769. The reversal of 638463764 is 467364836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638463769) 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 7 ways as a sum of consecutive naturals, for example, 245792 + ... + 248375.

It is an arithmetic number, because the mean of its divisors is an integer number (51887640).

Almost surely, 2^638463764 is an apocalyptic number.

It is an amenable number.

638463764 is a deficient number, since it is larger than the sum of its proper divisors (606839596).

638463764 is a wasteful number, since it uses less digits than its factorization.

638463764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 494207 (or 494205 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 47.

The square root of 638463764 is about 25267.8405092323. The cubic root of 638463764 is about 861.0837985439.

The spelling of 638463764 in words is "six hundred thirty-eight million, four hundred sixty-three thousand, seven hundred sixty-four".