638432 has 24 divisors (see below), whose sum is σ = 1279152. Its totient is φ = 313600.

The previous prime is 638431. The next prime is 638437. The reversal of 638432 is 234836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638431) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2132 + ... + 2412.

It is an arithmetic number, because the mean of its divisors is an integer number (53298).

2⁶³⁸⁴³² is an apocalyptic number.

It is an amenable number.

638432 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

638432 is a wasteful number, since it uses less digits than its factorization.

638432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362 (or 354 counting only the distinct ones).

The product of its digits is 3456, while the sum is 26.

The square root of 638432 is about 799.0193990136. The cubic root of 638432 is about 86.1069518475.

The spelling of 638432 in words is "six hundred thirty-eight thousand, four hundred thirty-two".