90138839 has 4 divisors (see below), whose sum is σ = 103015824. Its totient is φ = 77261856.

The previous prime is 90138827. The next prime is 90138871. The reversal of 90138839 is 93883109.

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

It is not a de Polignac number, because 90138839 - 2²⁰ = 89090263 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 90138796 and 90138805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90138889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6438482 + ... + 6438495.

It is an arithmetic number, because the mean of its divisors is an integer number (25753956).

Almost surely, 2^90138839 is an apocalyptic number.

90138839 is a deficient number, since it is larger than the sum of its proper divisors (12876985).

90138839 is a wasteful number, since it uses less digits than its factorization.

90138839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12876984.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 90138839 is about 9494.1476184016. The cubic root of 90138839 is about 448.3707983905.

The spelling of 90138839 in words is "ninety million, one hundred thirty-eight thousand, eight hundred thirty-nine".