91285863 has 4 divisors (see below), whose sum is σ = 121714488. Its totient is φ = 60857240.

The previous prime is 91285841. The next prime is 91285867. The reversal of 91285863 is 36858219.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36858219 = 3 ⋅12286073.

It is a cyclic number.

It is not a de Polignac number, because 91285863 - 2¹² = 91281767 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91285867) 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, 15214308 + ... + 15214313.

It is an arithmetic number, because the mean of its divisors is an integer number (30428622).

Almost surely, 2^91285863 is an apocalyptic number.

91285863 is a deficient number, since it is larger than the sum of its proper divisors (30428625).

91285863 is a wasteful number, since it uses less digits than its factorization.

91285863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30428624.

The product of its digits is 103680, while the sum is 42.

The square root of 91285863 is about 9554.3635580817. The cubic root of 91285863 is about 450.2646394001.

The spelling of 91285863 in words is "ninety-one million, two hundred eighty-five thousand, eight hundred sixty-three".