91845 has 24 divisors (see below), whose sum is σ = 172536. Its totient is φ = 44928.

The previous prime is 91841. The next prime is 91867. The reversal of 91845 is 54819.

It can be written as a sum of positive squares in 4 ways, for example, as 36 + 91809 = 6^2 + 303^2 .

It is not a de Polignac number, because 91845 - 2² = 91841 is a prime.

It is an Ulam number.

It is a Curzon number.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91841) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 507 + ... + 663.

It is an arithmetic number, because the mean of its divisors is an integer number (7189).

2⁹¹⁸⁴⁵ is an apocalyptic number.

It is an amenable number.

91845 is a deficient number, since it is larger than the sum of its proper divisors (80691).

91845 is a wasteful number, since it uses less digits than its factorization.

91845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181 (or 178 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 91845 is about 303.0594001182. The cubic root of 91845 is about 45.1182077340.

The spelling of 91845 in words is "ninety-one thousand, eight hundred forty-five".