91865161 has 4 divisors (see below), whose sum is σ = 97269012. Its totient is φ = 86461312.

The previous prime is 91865159. The next prime is 91865167. The reversal of 91865161 is 16156819.

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

It can be written as a sum of positive squares in 2 ways, for example, as 82446400 + 9418761 = 9080^2 + 3069^2 .

It is a cyclic number.

It is not a de Polignac number, because 91865161 - 2¹ = 91865159 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91865161.

It is not an unprimeable number, because it can be changed into a prime (91865167) 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, 2701900 + ... + 2701933.

It is an arithmetic number, because the mean of its divisors is an integer number (24317253).

Almost surely, 2^91865161 is an apocalyptic number.

It is an amenable number.

91865161 is a deficient number, since it is larger than the sum of its proper divisors (5403851).

91865161 is a wasteful number, since it uses less digits than its factorization.

91865161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5403850.

The product of its digits is 12960, while the sum is 37.

The square root of 91865161 is about 9584.6315004803. The cubic root of 91865161 is about 451.2150880877.

The spelling of 91865161 in words is "ninety-one million, eight hundred sixty-five thousand, one hundred sixty-one".