138624638 has 8 divisors (see below), whose sum is σ = 208228320. Its totient is φ = 69215200.

The previous prime is 138624637. The next prime is 138624643. The reversal of 138624638 is 836426831.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 138624595 and 138624604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138624631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46763 + ... + 49638.

It is an arithmetic number, because the mean of its divisors is an integer number (26028540).

Almost surely, 2^138624638 is an apocalyptic number.

138624638 is a deficient number, since it is larger than the sum of its proper divisors (69603682).

138624638 is an equidigital number, since it uses as much as digits as its factorization.

138624638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97122.

The product of its digits is 165888, while the sum is 41.

The square root of 138624638 is about 11773.8964663360. The cubic root of 138624638 is about 517.5434402300.

The spelling of 138624638 in words is "one hundred thirty-eight million, six hundred twenty-four thousand, six hundred thirty-eight".