138994985 has 16 divisors (see below), whose sum is σ = 168564240. Its totient is φ = 110023680.

The previous prime is 138994967. The next prime is 138994997. The reversal of 138994985 is 589499831.

It can be written as a sum of positive squares in 8 ways, for example, as 885481 + 138109504 = 941^2 + 11752^2 .

It is not a de Polignac number, because 138994985 - 2¹⁴ = 138978601 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138994985.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 266525 + ... + 267045.

It is an arithmetic number, because the mean of its divisors is an integer number (10535265).

Almost surely, 2^138994985 is an apocalyptic number.

It is an amenable number.

138994985 is a deficient number, since it is larger than the sum of its proper divisors (29569255).

138994985 is a wasteful number, since it uses less digits than its factorization.

138994985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 988.

The product of its digits is 2799360, while the sum is 56.

The square root of 138994985 is about 11789.6134372591. The cubic root of 138994985 is about 518.0039168768.

It can be divided in two parts, 13 and 8994985, that added together give a palindrome (8994998).

The spelling of 138994985 in words is "one hundred thirty-eight million, nine hundred ninety-four thousand, nine hundred eighty-five".