138833209 has 4 divisors (see below), whose sum is σ = 146140240. Its totient is φ = 131526180.

The previous prime is 138833183. The next prime is 138833239. The reversal of 138833209 is 902338831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 138833209 - 2⁷ = 138833081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138833239) 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 3 ways as a sum of consecutive naturals, for example, 3653487 + ... + 3653524.

It is an arithmetic number, because the mean of its divisors is an integer number (36535060).

Almost surely, 2^138833209 is an apocalyptic number.

138833209 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

138833209 is a deficient number, since it is larger than the sum of its proper divisors (7307031).

138833209 is an equidigital number, since it uses as much as digits as its factorization.

138833209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7307030.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 138833209 is about 11782.7504853493. The cubic root of 138833209 is about 517.8028709314.

The spelling of 138833209 in words is "one hundred thirty-eight million, eight hundred thirty-three thousand, two hundred nine".