91668089 has 2 divisors, whose sum is σ = 91668090. Its totient is φ = 91668088.

The previous prime is 91668079. The next prime is 91668113. The reversal of 91668089 is 98086619.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78765625 + 12902464 = 8875^2 + 3592^2 .

It is a cyclic number.

It is not a de Polignac number, because 91668089 - 2²⁰ = 90619513 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (91668079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45834044 + 45834045.

It is an arithmetic number, because the mean of its divisors is an integer number (45834045).

Almost surely, 2^91668089 is an apocalyptic number.

It is an amenable number.

91668089 is a deficient number, since it is larger than the sum of its proper divisors (1).

91668089 is an equidigital number, since it uses as much as digits as its factorization.

91668089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 47.

The square root of 91668089 is about 9574.3453562110. The cubic root of 91668089 is about 450.8922035442.

The spelling of 91668089 in words is "ninety-one million, six hundred sixty-eight thousand, eighty-nine".