638384769 has 24 divisors (see below), whose sum is σ = 1015185600. Its totient is φ = 383343840.

The previous prime is 638384737. The next prime is 638384809. The reversal of 638384769 is 967483836.

It is not a de Polignac number, because 638384769 - 2⁵ = 638384737 is a prime.

It is a super-2 number, since 2×638384769² = 815070226582366722, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (638383769) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 18789 + ... + 40370.

It is an arithmetic number, because the mean of its divisors is an integer number (42299400).

Almost surely, 2^638384769 is an apocalyptic number.

It is an amenable number.

638384769 is a deficient number, since it is larger than the sum of its proper divisors (376800831).

638384769 is a wasteful number, since it uses less digits than its factorization.

638384769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59285 (or 59282 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 54.

The square root of 638384769 is about 25266.2773079059. The cubic root of 638384769 is about 861.0482840668.

The spelling of 638384769 in words is "six hundred thirty-eight million, three hundred eighty-four thousand, seven hundred sixty-nine".