91149865 has 4 divisors (see below), whose sum is σ = 109379844. Its totient is φ = 72919888.

The previous prime is 91149829. The next prime is 91149887. The reversal of 91149865 is 56894119.

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 43705321 + 47444544 = 6611^2 + 6888^2 .

It is a cyclic number.

It is not a de Polignac number, because 91149865 - 2²³ = 82761257 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9114982 + ... + 9114991.

It is an arithmetic number, because the mean of its divisors is an integer number (27344961).

Almost surely, 2^91149865 is an apocalyptic number.

It is an amenable number.

91149865 is a deficient number, since it is larger than the sum of its proper divisors (18229979).

91149865 is a wasteful number, since it uses less digits than its factorization.

91149865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18229978.

The product of its digits is 77760, while the sum is 43.

The square root of 91149865 is about 9547.2438431204. The cubic root of 91149865 is about 450.0409263189.

The spelling of 91149865 in words is "ninety-one million, one hundred forty-nine thousand, eight hundred sixty-five".