638342208 has 280 divisors, whose sum is σ = 2212848000. Its totient is φ = 181875456.

The previous prime is 638342189. The next prime is 638342213. The reversal of 638342208 is 802243836.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1777933 + ... + 1778291.

Almost surely, 2^638342208 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 638342208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1106424000).

638342208 is an abundant number, since it is smaller than the sum of its proper divisors (1574505792).

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

638342208 is an equidigital number, since it uses as much as digits as its factorization.

638342208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404 (or 371 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 638342208 is about 25265.4350447405. The cubic root of 638342208 is about 861.0291483291.

The spelling of 638342208 in words is "six hundred thirty-eight million, three hundred forty-two thousand, two hundred eight".