91173965 has 4 divisors (see below), whose sum is σ = 109408764. Its totient is φ = 72939168.

The previous prime is 91173961. The next prime is 91173967. The reversal of 91173965 is 56937119.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56937119 = 4871 ⋅11689.

It can be written as a sum of positive squares in 2 ways, for example, as 18003049 + 73170916 = 4243^2 + 8554^2 .

It is a cyclic number.

It is not a de Polignac number, because 91173965 - 2² = 91173961 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91173961) 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, 9117392 + ... + 9117401.

It is an arithmetic number, because the mean of its divisors is an integer number (27352191).

Almost surely, 2^91173965 is an apocalyptic number.

It is an amenable number.

91173965 is a deficient number, since it is larger than the sum of its proper divisors (18234799).

91173965 is a wasteful number, since it uses less digits than its factorization.

91173965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18234798.

The product of its digits is 51030, while the sum is 41.

The square root of 91173965 is about 9548.5059040669. The cubic root of 91173965 is about 450.0805863907.

The spelling of 91173965 in words is "ninety-one million, one hundred seventy-three thousand, nine hundred sixty-five".