638013318 has 16 divisors (see below), whose sum is σ = 1276306416. Its totient is φ = 212624480.

The previous prime is 638013301. The next prime is 638013323. The reversal of 638013318 is 813310836.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28780 + ... + 45872.

It is an arithmetic number, because the mean of its divisors is an integer number (79769151).

Almost surely, 2^638013318 is an apocalyptic number.

638013318 is an abundant number, since it is smaller than the sum of its proper divisors (638293098).

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

638013318 is a wasteful number, since it uses less digits than its factorization.

638013318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23319.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 638013318 is about 25258.9255115890. The cubic root of 638013318 is about 860.8812482835.

The spelling of 638013318 in words is "six hundred thirty-eight million, thirteen thousand, three hundred eighteen".