638471824 has 15 divisors (see below), whose sum is σ = 1237235017. Its totient is φ = 319185376.

The previous prime is 638471819. The next prime is 638471843. The reversal of 638471824 is 428174836.

The square root of 638471824 is 25268.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 343731600 + 294740224 = 18540^2 + 17168^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 97914 + ... + 104230.

Almost surely, 2^638471824 is an apocalyptic number.

638471824 is the 25268-th square number.

It is an amenable number.

638471824 is a deficient number, since it is larger than the sum of its proper divisors (598763193).

638471824 is an frugal number, since it uses more digits than its factorization.

638471824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12642 (or 6319 counting only the distinct ones).

The product of its digits is 258048, while the sum is 43.

The cubic root of 638471824 is about 861.0874219843.

The spelling of 638471824 in words is "six hundred thirty-eight million, four hundred seventy-one thousand, eight hundred twenty-four".