421638388 has 12 divisors (see below), whose sum is σ = 738052000. Its totient is φ = 210766392.

The previous prime is 421638377. The next prime is 421638397. The reversal of 421638388 is 883836124.

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8863 + ... + 30361.

Almost surely, 2^421638388 is an apocalyptic number.

It is an amenable number.

421638388 is a deficient number, since it is larger than the sum of its proper divisors (316413612).

421638388 is a wasteful number, since it uses less digits than its factorization.

421638388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26406 (or 26404 counting only the distinct ones).

The product of its digits is 221184, while the sum is 43.

The square root of 421638388 is about 20533.8351994945. The cubic root of 421638388 is about 749.8597592598.

The spelling of 421638388 in words is "four hundred twenty-one million, six hundred thirty-eight thousand, three hundred eighty-eight".