91665801 has 12 divisors (see below), whose sum is σ = 132678000. Its totient is φ = 60985080.

The previous prime is 91665797. The next prime is 91665803. The reversal of 91665801 is 10856619.

It is not a de Polignac number, because 91665801 - 2² = 91665797 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (91665803) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5715 + ... + 14696.

It is an arithmetic number, because the mean of its divisors is an integer number (11056500).

Almost surely, 2^91665801 is an apocalyptic number.

It is an amenable number.

91665801 is a deficient number, since it is larger than the sum of its proper divisors (41012199).

91665801 is a wasteful number, since it uses less digits than its factorization.

91665801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20916 (or 20913 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 91665801 is about 9574.2258694894. The cubic root of 91665801 is about 450.8884521481. Note that the first 3 decimals are identical.

The spelling of 91665801 in words is "ninety-one million, six hundred sixty-five thousand, eight hundred one".