638195504 has 80 divisors (see below), whose sum is σ = 1358350560. Its totient is φ = 289259520.

The previous prime is 638195497. The next prime is 638195533. The reversal of 638195504 is 405591836.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 992207 + ... + 992849.

It is an arithmetic number, because the mean of its divisors is an integer number (16979382).

Almost surely, 2^638195504 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638195504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (679175280).

638195504 is an abundant number, since it is smaller than the sum of its proper divisors (720155056).

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

638195504 is a wasteful number, since it uses less digits than its factorization.

638195504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 798 (or 792 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 41.

The square root of 638195504 is about 25262.5316229391. The cubic root of 638195504 is about 860.9631826153.

The spelling of 638195504 in words is "six hundred thirty-eight million, one hundred ninety-five thousand, five hundred four".