638238814 has 4 divisors (see below), whose sum is σ = 957358224. Its totient is φ = 319119406.

The previous prime is 638238787. The next prime is 638238857. The reversal of 638238814 is 418832836.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×638238814² = 814697567392253192, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159559702 + ... + 159559705.

It is an arithmetic number, because the mean of its divisors is an integer number (239339556).

Almost surely, 2^638238814 is an apocalyptic number.

638238814 is a deficient number, since it is larger than the sum of its proper divisors (319119410).

638238814 is a wasteful number, since it uses less digits than its factorization.

638238814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319119409.

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

The square root of 638238814 is about 25263.3888067298. The cubic root of 638238814 is about 860.9826580852.

The spelling of 638238814 in words is "six hundred thirty-eight million, two hundred thirty-eight thousand, eight hundred fourteen".