138538859 has 4 divisors (see below), whose sum is σ = 139468800. Its totient is φ = 137608920.

The previous prime is 138538853. The next prime is 138538879. The reversal of 138538859 is 958835831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 958835831 = 109 ⋅8796659.

It is a cyclic number.

It is not a de Polignac number, because 138538859 - 2²⁴ = 121761643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138538853) 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, 464747 + ... + 465044.

It is an arithmetic number, because the mean of its divisors is an integer number (34867200).

Almost surely, 2^138538859 is an apocalyptic number.

138538859 is a deficient number, since it is larger than the sum of its proper divisors (929941).

138538859 is an equidigital number, since it uses as much as digits as its factorization.

138538859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 929940.

The product of its digits is 1036800, while the sum is 50.

The square root of 138538859 is about 11770.2531408632. The cubic root of 138538859 is about 517.4366686406.

The spelling of 138538859 in words is "one hundred thirty-eight million, five hundred thirty-eight thousand, eight hundred fifty-nine".