138243233 has 2 divisors, whose sum is σ = 138243234. Its totient is φ = 138243232.

The previous prime is 138243197. The next prime is 138243247. The reversal of 138243233 is 332342831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138133009 + 110224 = 11753^2 + 332^2 .

It is a cyclic number.

It is not a de Polignac number, because 138243233 - 2¹⁸ = 137981089 is a prime.

It is a super-2 number, since 2×138243233² = 38222382940584578, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138243196 and 138243205.

It is not a weakly prime, because it can be changed into another prime (138243293) 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 as a sum of consecutive naturals, namely, 69121616 + 69121617.

It is an arithmetic number, because the mean of its divisors is an integer number (69121617).

Almost surely, 2^138243233 is an apocalyptic number.

It is an amenable number.

138243233 is a deficient number, since it is larger than the sum of its proper divisors (1).

138243233 is an equidigital number, since it uses as much as digits as its factorization.

138243233 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 29.

The square root of 138243233 is about 11757.6882506724. The cubic root of 138243233 is about 517.0683564138.

The spelling of 138243233 in words is "one hundred thirty-eight million, two hundred forty-three thousand, two hundred thirty-three".