638402274 has 24 divisors (see below), whose sum is σ = 1384214832. Its totient is φ = 212645400.

The previous prime is 638402263. The next prime is 638402279. The reversal of 638402274 is 472204836.

638402274 is a `hidden beast` number, since 6 + 384 + 0 + 2 + 274 = 666.

638402274 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×638402274³ (a number of 27 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (638402279) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13897 + ... + 38339.

It is an arithmetic number, because the mean of its divisors is an integer number (57675618).

Almost surely, 2^638402274 is an apocalyptic number.

638402274 is an abundant number, since it is smaller than the sum of its proper divisors (745812558).

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

638402274 is a wasteful number, since it uses less digits than its factorization.

638402274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25902 (or 25899 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The square root of 638402274 is about 25266.6237158826. The cubic root of 638402274 is about 861.0561541963.

The spelling of 638402274 in words is "six hundred thirty-eight million, four hundred two thousand, two hundred seventy-four".