638201264 has 40 divisors (see below), whose sum is σ = 1264294080. Its totient is φ = 312003648.

The previous prime is 638201261. The next prime is 638201273. The reversal of 638201264 is 462102836.

It is a self number, because there is not a number n which added to its sum of digits gives 638201264.

It is not an unprimeable number, because it can be changed into a prime (638201261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 146867 + ... + 151149.

It is an arithmetic number, because the mean of its divisors is an integer number (31607352).

Almost surely, 2^638201264 is an apocalyptic number.

It is an amenable number.

638201264 is a deficient number, since it is larger than the sum of its proper divisors (626092816).

638201264 is a wasteful number, since it uses less digits than its factorization.

638201264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4497 (or 4491 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 32.

The square root of 638201264 is about 25262.6456255080. The cubic root of 638201264 is about 860.9657728002.

The spelling of 638201264 in words is "six hundred thirty-eight million, two hundred one thousand, two hundred sixty-four".