138509579 has 8 divisors (see below), whose sum is σ = 152633712. Its totient is φ = 124881120.

The previous prime is 138509573. The next prime is 138509621. The reversal of 138509579 is 975905831.

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

It is not a de Polignac number, because 138509579 - 2²⁰ = 137461003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138509573) 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, 123332 + ... + 124449.

It is an arithmetic number, because the mean of its divisors is an integer number (19079214).

Almost surely, 2^138509579 is an apocalyptic number.

138509579 is a deficient number, since it is larger than the sum of its proper divisors (14124133).

138509579 is a wasteful number, since it uses less digits than its factorization.

138509579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247837.

The product of its (nonzero) digits is 340200, while the sum is 47.

The square root of 138509579 is about 11769.0092616159. The cubic root of 138509579 is about 517.4002128927.

The spelling of 138509579 in words is "one hundred thirty-eight million, five hundred nine thousand, five hundred seventy-nine".