138318233 has 6 divisors (see below), whose sum is σ = 145981674. Its totient is φ = 131037984.

The previous prime is 138318221. The next prime is 138318241. The reversal of 138318233 is 332813831.

It can be written as a sum of positive squares in only one way, i.e., 122699929 + 15618304 = 11077^2 + 3952^2 .

It is a de Polignac number, because none of the positive numbers 2^k-138318233 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138318233.

It is not an unprimeable number, because it can be changed into a prime (138318253) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 191216 + ... + 191937.

It is an arithmetic number, because the mean of its divisors is an integer number (24330279).

Almost surely, 2^138318233 is an apocalyptic number.

It is an amenable number.

138318233 is a deficient number, since it is larger than the sum of its proper divisors (7663441).

138318233 is an equidigital number, since it uses as much as digits as its factorization.

138318233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383191 (or 383172 counting only the distinct ones).

The product of its digits is 10368, while the sum is 32.

The square root of 138318233 is about 11760.8772206838. The cubic root of 138318233 is about 517.1618465012.

The spelling of 138318233 in words is "one hundred thirty-eight million, three hundred eighteen thousand, two hundred thirty-three".