138805585 has 4 divisors (see below), whose sum is σ = 166566708. Its totient is φ = 111044464.

The previous prime is 138805573. The next prime is 138805603. The reversal of 138805585 is 585508831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 585508831 = 37 ⋅15824563.

It can be written as a sum of positive squares in 2 ways, for example, as 89567296 + 49238289 = 9464^2 + 7017^2 .

It is a cyclic number.

It is not a de Polignac number, because 138805585 - 2⁵ = 138805553 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13880554 + ... + 13880563.

It is an arithmetic number, because the mean of its divisors is an integer number (41641677).

Almost surely, 2^138805585 is an apocalyptic number.

It is an amenable number.

138805585 is a deficient number, since it is larger than the sum of its proper divisors (27761123).

138805585 is an equidigital number, since it uses as much as digits as its factorization.

138805585 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27761122.

The product of its (nonzero) digits is 192000, while the sum is 43.

The square root of 138805585 is about 11781.5782049775. The cubic root of 138805585 is about 517.7685257979.

The spelling of 138805585 in words is "one hundred thirty-eight million, eight hundred five thousand, five hundred eighty-five".