138528685 has 8 divisors (see below), whose sum is σ = 166536216. Its totient is φ = 110621760.

The previous prime is 138528667. The next prime is 138528713. The reversal of 138528685 is 586825831.

It can be written as a sum of positive squares in 4 ways, for example, as 15163236 + 123365449 = 3894^2 + 11107^2 .

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

It is not a de Polignac number, because 138528685 - 2¹¹ = 138526637 is a prime.

It is a Duffinian number.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 22086 + ... + 27655.

It is an arithmetic number, because the mean of its divisors is an integer number (20817027).

Almost surely, 2^138528685 is an apocalyptic number.

It is an amenable number.

138528685 is a deficient number, since it is larger than the sum of its proper divisors (28007531).

138528685 is an equidigital number, since it uses as much as digits as its factorization.

138528685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50303.

The product of its digits is 460800, while the sum is 46.

The square root of 138528685 is about 11769.8209417136. The cubic root of 138528685 is about 517.4240018467.

The spelling of 138528685 in words is "one hundred thirty-eight million, five hundred twenty-eight thousand, six hundred eighty-five".