138368731 has 4 divisors (see below), whose sum is σ = 138734200. Its totient is φ = 138003264.

The previous prime is 138368723. The next prime is 138368753. The reversal of 138368731 is 137863831.

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 138368731 - 2³ = 138368723 is a prime.

It is a super-2 number, since 2×138368731² = 38291811437100722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138360731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 182166 + ... + 182923.

It is an arithmetic number, because the mean of its divisors is an integer number (34683550).

Almost surely, 2^138368731 is an apocalyptic number.

138368731 is a deficient number, since it is larger than the sum of its proper divisors (365469).

138368731 is an equidigital number, since it uses as much as digits as its factorization.

138368731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365468.

The product of its digits is 72576, while the sum is 40.

The square root of 138368731 is about 11763.0238884396. The cubic root of 138368731 is about 517.2247749642.

The spelling of 138368731 in words is "one hundred thirty-eight million, three hundred sixty-eight thousand, seven hundred thirty-one".