91166591 has 2 divisors, whose sum is σ = 91166592. Its totient is φ = 91166590.

The previous prime is 91166587. The next prime is 91166651. The reversal of 91166591 is 19566119.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91166591 - 2² = 91166587 is a prime.

It is a super-2 number, since 2×91166591² = 16622694629122562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91166791) by changing a digit.

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 as a sum of consecutive naturals, namely, 45583295 + 45583296.

It is an arithmetic number, because the mean of its divisors is an integer number (45583296).

Almost surely, 2^91166591 is an apocalyptic number.

91166591 is a deficient number, since it is larger than the sum of its proper divisors (1).

91166591 is an equidigital number, since it uses as much as digits as its factorization.

91166591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14580, while the sum is 38.

The square root of 91166591 is about 9548.1197625501. The cubic root of 91166591 is about 450.0684521383.

The spelling of 91166591 in words is "ninety-one million, one hundred sixty-six thousand, five hundred ninety-one".