138123818 has 16 divisors (see below), whose sum is σ = 236934720. Its totient is φ = 59158176.

The previous prime is 138123761. The next prime is 138123823. The reversal of 138123818 is 818321831.

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 7 ways as a sum of consecutive naturals, for example, 39905 + ... + 43227.

It is an arithmetic number, because the mean of its divisors is an integer number (14808420).

Almost surely, 2^138123818 is an apocalyptic number.

138123818 is a deficient number, since it is larger than the sum of its proper divisors (98810902).

138123818 is a wasteful number, since it uses less digits than its factorization.

138123818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6301.

The product of its digits is 9216, while the sum is 35.

The square root of 138123818 is about 11752.6089869441. The cubic root of 138123818 is about 516.9194316920.

The spelling of 138123818 in words is "one hundred thirty-eight million, one hundred twenty-three thousand, eight hundred eighteen".