91806811 has 4 divisors (see below), whose sum is σ = 91941912. Its totient is φ = 91671712.

The previous prime is 91806809. The next prime is 91806821. The reversal of 91806811 is 11860819.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91806811 - 2¹ = 91806809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91806821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66526 + ... + 67891.

It is an arithmetic number, because the mean of its divisors is an integer number (22985478).

Almost surely, 2^91806811 is an apocalyptic number.

91806811 is a deficient number, since it is larger than the sum of its proper divisors (135101).

91806811 is a wasteful number, since it uses less digits than its factorization.

91806811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135100.

The product of its (nonzero) digits is 3456, while the sum is 34.

The square root of 91806811 is about 9581.5870814808. The cubic root of 91806811 is about 451.1195350822.

The spelling of 91806811 in words is "ninety-one million, eight hundred six thousand, eight hundred eleven".