638470 has 24 divisors (see below), whose sum is σ = 1337904. Its totient is φ = 218736.

The previous prime is 638467. The next prime is 638489. The reversal of 638470 is 74836.

638470 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 162 + ... + 1141.

It is an arithmetic number, because the mean of its divisors is an integer number (55746).

2⁶³⁸⁴⁷⁰ is an apocalyptic number.

638470 is an abundant number, since it is smaller than the sum of its proper divisors (699434).

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

638470 is a wasteful number, since it uses less digits than its factorization.

638470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1324 (or 1317 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 638470 is about 799.0431778071. The cubic root of 638470 is about 86.1086601993.

The spelling of 638470 in words is "six hundred thirty-eight thousand, four hundred seventy".