638876736 has 42 divisors (see below), whose sum is σ = 1831226462. Its totient is φ = 212958720.

The previous prime is 638876731. The next prime is 638876747. The reversal of 638876736 is 637678836.

It can be written as a sum of positive squares in only one way, i.e., 525326400 + 113550336 = 22920^2 + 10656^2 .

It is not an unprimeable number, because it can be changed into a prime (638876731) by changing a digit.

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 in 5 ways as a sum of consecutive naturals, for example, 554005 + ... + 555156.

Almost surely, 2^638876736 is an apocalyptic number.

It is an amenable number.

638876736 is an abundant number, since it is smaller than the sum of its proper divisors (1192349726).

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

638876736 is a wasteful number, since it uses less digits than its factorization.

638876736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1109179 (or 1109166 counting only the distinct ones).

The product of its digits is 6096384, while the sum is 54.

The square root of 638876736 is about 25276.0110776997. The cubic root of 638876736 is about 861.2694143274.

The spelling of 638876736 in words is "six hundred thirty-eight million, eight hundred seventy-six thousand, seven hundred thirty-six".