138933247 has 4 divisors (see below), whose sum is σ = 139701016. Its totient is φ = 138165480.

The previous prime is 138933241. The next prime is 138933251. The reversal of 138933247 is 742339831.

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

It is a cyclic number.

It is not a de Polignac number, because 138933247 - 2³ = 138933239 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138933241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 383613 + ... + 383974.

It is an arithmetic number, because the mean of its divisors is an integer number (34925254).

Almost surely, 2^138933247 is an apocalyptic number.

138933247 is a deficient number, since it is larger than the sum of its proper divisors (767769).

138933247 is an equidigital number, since it uses as much as digits as its factorization.

138933247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 767768.

The product of its digits is 108864, while the sum is 40.

The square root of 138933247 is about 11786.9948248059. The cubic root of 138933247 is about 517.9272108432.

The spelling of 138933247 in words is "one hundred thirty-eight million, nine hundred thirty-three thousand, two hundred forty-seven".