638489528 has 32 divisors (see below), whose sum is σ = 1262208000. Its totient is φ = 301955040.

The previous prime is 638489521. The next prime is 638489539. The reversal of 638489528 is 825984836.

It is a self number, because there is not a number n which added to its sum of digits gives 638489528.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638489521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101993 + ... + 108071.

It is an arithmetic number, because the mean of its divisors is an integer number (39444000).

Almost surely, 2^638489528 is an apocalyptic number.

It is an amenable number.

638489528 is a deficient number, since it is larger than the sum of its proper divisors (623718472).

638489528 is a wasteful number, since it uses less digits than its factorization.

638489528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6795 (or 6791 counting only the distinct ones).

The product of its digits is 3317760, while the sum is 53.

The square root of 638489528 is about 25268.3503220927. The cubic root of 638489528 is about 861.0953808585.

The spelling of 638489528 in words is "six hundred thirty-eight million, four hundred eighty-nine thousand, five hundred twenty-eight".