638383836 has 12 divisors (see below), whose sum is σ = 1489562312. Its totient is φ = 212794608.

The previous prime is 638383807. The next prime is 638383843.

638383836 is nontrivially palindromic in base 10.

It is a tau number, because it is divible by the number of its divisors (12).

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26599315 + ... + 26599338.

Almost surely, 2^638383836 is an apocalyptic number.

It is an amenable number.

638383836 is an abundant number, since it is smaller than the sum of its proper divisors (851178476).

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

638383836 is a wasteful number, since it uses less digits than its factorization.

638383836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53198660 (or 53198658 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 48.

The square root of 638383836 is about 25266.2588445539. The cubic root of 638383836 is about 861.0478645923.

The spelling of 638383836 in words is "six hundred thirty-eight million, three hundred eighty-three thousand, eight hundred thirty-six".