91318385 has 4 divisors (see below), whose sum is σ = 109582068. Its totient is φ = 73054704.

The previous prime is 91318379. The next prime is 91318393. The reversal of 91318385 is 58381319.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58381319 = 19 ⋅3072701.

It can be written as a sum of positive squares in 2 ways, for example, as 57259489 + 34058896 = 7567^2 + 5836^2 .

It is a cyclic number.

It is not a de Polignac number, because 91318385 - 2²⁴ = 74541169 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9131834 + ... + 9131843.

It is an arithmetic number, because the mean of its divisors is an integer number (27395517).

Almost surely, 2^91318385 is an apocalyptic number.

It is an amenable number.

91318385 is a deficient number, since it is larger than the sum of its proper divisors (18263683).

91318385 is a wasteful number, since it uses less digits than its factorization.

91318385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18263682.

The product of its digits is 25920, while the sum is 38.

The square root of 91318385 is about 9556.0653513881. The cubic root of 91318385 is about 450.3181042977.

The spelling of 91318385 in words is "ninety-one million, three hundred eighteen thousand, three hundred eighty-five".