138163731 has 4 divisors (see below), whose sum is σ = 184218312. Its totient is φ = 92109152.

The previous prime is 138163721. The next prime is 138163741. The reversal of 138163731 is 137361831.

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

It is an interprime number because it is at equal distance from previous prime (138163721) and next prime (138163741).

It is a cyclic number.

It is not a de Polignac number, because 138163731 - 2⁷ = 138163603 is a prime.

It is a super-2 number, since 2×138163731² = 38178433127680722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138163692 and 138163701.

It is not an unprimeable number, because it can be changed into a prime (138163721) 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, 23027286 + ... + 23027291.

It is an arithmetic number, because the mean of its divisors is an integer number (46054578).

Almost surely, 2^138163731 is an apocalyptic number.

138163731 is a deficient number, since it is larger than the sum of its proper divisors (46054581).

138163731 is an equidigital number, since it uses as much as digits as its factorization.

138163731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46054580.

The product of its digits is 9072, while the sum is 33.

The square root of 138163731 is about 11754.3069127873. The cubic root of 138163731 is about 516.9692175016.

The spelling of 138163731 in words is "one hundred thirty-eight million, one hundred sixty-three thousand, seven hundred thirty-one".