91668618 has 32 divisors (see below), whose sum is σ = 205211520. Its totient is φ = 30330720.

The previous prime is 91668613. The next prime is 91668637. The reversal of 91668618 is 81686619.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (91668613) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1203 + ... + 13593.

It is an arithmetic number, because the mean of its divisors is an integer number (6412860).

Almost surely, 2^91668618 is an apocalyptic number.

91668618 is an abundant number, since it is smaller than the sum of its proper divisors (113542902).

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

91668618 is a wasteful number, since it uses less digits than its factorization.

91668618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12539 (or 12533 counting only the distinct ones).

The product of its digits is 124416, while the sum is 45.

The square root of 91668618 is about 9574.3729820809. The cubic root of 91668618 is about 450.8930708817.

The spelling of 91668618 in words is "ninety-one million, six hundred sixty-eight thousand, six hundred eighteen".