138609635 has 4 divisors (see below), whose sum is σ = 166331568. Its totient is φ = 110887704.

The previous prime is 138609607. The next prime is 138609641. The reversal of 138609635 is 536906831.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 138609635 - 2⁶ = 138609571 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138609592 and 138609601.

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 3 ways as a sum of consecutive naturals, for example, 13860959 + ... + 13860968.

It is an arithmetic number, because the mean of its divisors is an integer number (41582892).

Almost surely, 2^138609635 is an apocalyptic number.

138609635 is a deficient number, since it is larger than the sum of its proper divisors (27721933).

138609635 is an equidigital number, since it uses as much as digits as its factorization.

138609635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27721932.

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 138609635 is about 11773.2593193219. The cubic root of 138609635 is about 517.5247687430.

The spelling of 138609635 in words is "one hundred thirty-eight million, six hundred nine thousand, six hundred thirty-five".