91938138 has 16 divisors (see below), whose sum is σ = 184291200. Its totient is φ = 30576896.

The previous prime is 91938089. The next prime is 91938151. The reversal of 91938138 is 83183919.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 91938138.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 14370 + ... + 19757.

It is an arithmetic number, because the mean of its divisors is an integer number (11518200).

Almost surely, 2^91938138 is an apocalyptic number.

91938138 is an abundant number, since it is smaller than the sum of its proper divisors (92353062).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91938138 is a wasteful number, since it uses less digits than its factorization.

91938138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34581.

The product of its digits is 46656, while the sum is 42.

The square root of 91938138 is about 9588.4377246765. The cubic root of 91938138 is about 451.3345370991.

The spelling of 91938138 in words is "ninety-one million, nine hundred thirty-eight thousand, one hundred thirty-eight".