91389186685 has 12 divisors (see below), whose sum is σ = 113579051508. Its totient is φ = 70590265088.

The previous prime is 91389186661. The next prime is 91389186739. The reversal of 91389186685 is 58668198319.

It can be written as a sum of positive squares in 6 ways, for example, as 4786702596 + 86602484089 = 69186^2 + 294283^2 .

It is not a de Polignac number, because 91389186685 - 2¹¹ = 91389184637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10862524 + ... + 10870933.

It is an arithmetic number, because the mean of its divisors is an integer number (9464920959).

Almost surely, 2^91389186685 is an apocalyptic number.

It is an amenable number.

91389186685 is a deficient number, since it is larger than the sum of its proper divisors (22189864823).

91389186685 is a wasteful number, since it uses less digits than its factorization.

91389186685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21733520 (or 21733491 counting only the distinct ones).

The product of its digits is 22394880, while the sum is 64.

The spelling of 91389186685 in words is "ninety-one billion, three hundred eighty-nine million, one hundred eighty-six thousand, six hundred eighty-five".