91664481 has 8 divisors (see below), whose sum is σ = 122273280. Its totient is φ = 61082672.

The previous prime is 91664477. The next prime is 91664491. The reversal of 91664481 is 18446619.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91664481 - 2² = 91664477 is a prime.

It is a super-2 number, since 2×91664481² = 16804754153998722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91664431) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 3331 + ... + 13943.

It is an arithmetic number, because the mean of its divisors is an integer number (15284160).

Almost surely, 2^91664481 is an apocalyptic number.

It is an amenable number.

91664481 is a deficient number, since it is larger than the sum of its proper divisors (30608799).

91664481 is a wasteful number, since it uses less digits than its factorization.

91664481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13495.

The product of its digits is 41472, while the sum is 39.

The square root of 91664481 is about 9574.1569341640. The cubic root of 91664481 is about 450.8862878527.

The spelling of 91664481 in words is "ninety-one million, six hundred sixty-four thousand, four hundred eighty-one".