638958396 has 24 divisors (see below), whose sum is σ = 1578603600. Its totient is φ = 200457472.

The previous prime is 638958367. The next prime is 638958409. The reversal of 638958396 is 693859836.

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, 1565871 + ... + 1566278.

It is an arithmetic number, because the mean of its divisors is an integer number (65775150).

Almost surely, 2^638958396 is an apocalyptic number.

It is an amenable number.

638958396 is an abundant number, since it is smaller than the sum of its proper divisors (939645204).

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

638958396 is a wasteful number, since it uses less digits than its factorization.

638958396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3132173 (or 3132171 counting only the distinct ones).

The product of its digits is 8398080, while the sum is 57.

The square root of 638958396 is about 25277.6263917323. The cubic root of 638958396 is about 861.3061080327.

The spelling of 638958396 in words is "six hundred thirty-eight million, nine hundred fifty-eight thousand, three hundred ninety-six".