638437952 has 14 divisors (see below), whose sum is σ = 1266900438. Its totient is φ = 319218944.

The previous prime is 638437939. The next prime is 638437973. The reversal of 638437952 is 259734836.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 394578496 + 243859456 = 19864^2 + 15616^2 .

It is a junction number, because it is equal to n+sod(n) for n = 638437897 and 638437906.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4987733 + ... + 4987860.

Almost surely, 2^638437952 is an apocalyptic number.

It is an amenable number.

638437952 is a deficient number, since it is larger than the sum of its proper divisors (628462486).

638437952 is an equidigital number, since it uses as much as digits as its factorization.

638437952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9975605 (or 9975595 counting only the distinct ones).

The product of its digits is 1088640, while the sum is 47.

The square root of 638437952 is about 25267.3297362424. The cubic root of 638437952 is about 861.0721943382.

The spelling of 638437952 in words is "six hundred thirty-eight million, four hundred thirty-seven thousand, nine hundred fifty-two".