138759209 has 8 divisors (see below), whose sum is σ = 141321120. Its totient is φ = 136204416.

The previous prime is 138759199. The next prime is 138759227. The reversal of 138759209 is 902957831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 138759209 - 2⁸ = 138758953 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 138759209.

It is not an unprimeable number, because it can be changed into a prime (138729209) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52217 + ... + 54809.

It is an arithmetic number, because the mean of its divisors is an integer number (17665140).

Almost surely, 2^138759209 is an apocalyptic number.

It is an amenable number.

138759209 is a deficient number, since it is larger than the sum of its proper divisors (2561911).

138759209 is an equidigital number, since it uses as much as digits as its factorization.

138759209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3559.

The product of its (nonzero) digits is 136080, while the sum is 44.

The square root of 138759209 is about 11779.6098831837. The cubic root of 138759209 is about 517.7108559094.

The spelling of 138759209 in words is "one hundred thirty-eight million, seven hundred fifty-nine thousand, two hundred nine".