138209359 has 4 divisors (see below), whose sum is σ = 139874616. Its totient is φ = 136544104.

The previous prime is 138209341. The next prime is 138209399. The reversal of 138209359 is 953902831.

138209359 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 138209359 - 2⁵ = 138209327 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138209339) 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, 832504 + ... + 832669.

It is an arithmetic number, because the mean of its divisors is an integer number (34968654).

Almost surely, 2^138209359 is an apocalyptic number.

138209359 is a deficient number, since it is larger than the sum of its proper divisors (1665257).

138209359 is an equidigital number, since it uses as much as digits as its factorization.

138209359 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1665256.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 138209359 is about 11756.2476581603. The cubic root of 138209359 is about 517.0261202192.

The spelling of 138209359 in words is "one hundred thirty-eight million, two hundred nine thousand, three hundred fifty-nine".