138879985 has 16 divisors (see below), whose sum is σ = 173571840. Its totient is φ = 106545600.

The previous prime is 138879943. The next prime is 138879991. The reversal of 138879985 is 589978831.

It is not a de Polignac number, because 138879985 - 2¹⁵ = 138847217 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 18724 + ... + 25066.

It is an arithmetic number, because the mean of its divisors is an integer number (10848240).

Almost surely, 2^138879985 is an apocalyptic number.

It is an amenable number.

138879985 is a deficient number, since it is larger than the sum of its proper divisors (34691855).

138879985 is a wasteful number, since it uses less digits than its factorization.

138879985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6528.

The product of its digits is 4354560, while the sum is 58.

The square root of 138879985 is about 11784.7352537085. The cubic root of 138879985 is about 517.8610175080.

The spelling of 138879985 in words is "one hundred thirty-eight million, eight hundred seventy-nine thousand, nine hundred eighty-five".