638955320 has 16 divisors (see below), whose sum is σ = 1437649560. Its totient is φ = 255582112.

The previous prime is 638955311. The next prime is 638955323. The reversal of 638955320 is 23559836.

638955320 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638955323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7986902 + ... + 7986981.

Almost surely, 2^638955320 is an apocalyptic number.

It is an amenable number.

638955320 is an abundant number, since it is smaller than the sum of its proper divisors (798694240).

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

638955320 is a wasteful number, since it uses less digits than its factorization.

638955320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15973894 (or 15973890 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 41.

The square root of 638955320 is about 25277.5655473386. The cubic root of 638955320 is about 861.3047258969.

The spelling of 638955320 in words is "six hundred thirty-eight million, nine hundred fifty-five thousand, three hundred twenty".