138840635 has 4 divisors (see below), whose sum is σ = 166608768. Its totient is φ = 111072504.

The previous prime is 138840607. The next prime is 138840707. The reversal of 138840635 is 536048831.

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 138840635 - 2¹² = 138836539 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, 13884059 + ... + 13884068.

It is an arithmetic number, because the mean of its divisors is an integer number (41652192).

Almost surely, 2^138840635 is an apocalyptic number.

138840635 is a deficient number, since it is larger than the sum of its proper divisors (27768133).

138840635 is an equidigital number, since it uses as much as digits as its factorization.

138840635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27768132.

The product of its (nonzero) digits is 69120, while the sum is 38.

The square root of 138840635 is about 11783.0656028047. The cubic root of 138840635 is about 517.8121029579.

The spelling of 138840635 in words is "one hundred thirty-eight million, eight hundred forty thousand, six hundred thirty-five".