638695272 has 16 divisors (see below), whose sum is σ = 1596738240. Its totient is φ = 212898416.

The previous prime is 638695271. The next prime is 638695289. The reversal of 638695272 is 272596836.

It is not an unprimeable number, because it can be changed into a prime (638695271) 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, 13306128 + ... + 13306175.

It is an arithmetic number, because the mean of its divisors is an integer number (99796140).

Almost surely, 2^638695272 is an apocalyptic number.

It is an amenable number.

638695272 is an abundant number, since it is smaller than the sum of its proper divisors (958042968).

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

638695272 is a wasteful number, since it uses less digits than its factorization.

638695272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26612312 (or 26612308 counting only the distinct ones).

The product of its digits is 1088640, while the sum is 48.

The square root of 638695272 is about 25272.4211740783. The cubic root of 638695272 is about 861.1878627626.

The spelling of 638695272 in words is "six hundred thirty-eight million, six hundred ninety-five thousand, two hundred seventy-two".