638387344 has 80 divisors (see below), whose sum is σ = 1464414208. Its totient is φ = 263886336.

The previous prime is 638387339. The next prime is 638387369. The reversal of 638387344 is 443783836.

It is a junction number, because it is equal to n+sod(n) for n = 638387294 and 638387303.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 525682 + ... + 526894.

Almost surely, 2^638387344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638387344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (732207104).

638387344 is an abundant number, since it is smaller than the sum of its proper divisors (826026864).

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

638387344 is a wasteful number, since it uses less digits than its factorization.

638387344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1392 (or 1386 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 46.

The square root of 638387344 is about 25266.3282651041. The cubic root of 638387344 is about 861.0494417784.

The spelling of 638387344 in words is "six hundred thirty-eight million, three hundred eighty-seven thousand, three hundred forty-four".