91022291 has 4 divisors (see below), whose sum is σ = 91827912. Its totient is φ = 90216672.

The previous prime is 91022273. The next prime is 91022333. The reversal of 91022291 is 19222019.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 91022291 - 2⁶ = 91022227 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 91022291.

It is not an unprimeable number, because it can be changed into a prime (91024291) 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, 402641 + ... + 402866.

It is an arithmetic number, because the mean of its divisors is an integer number (22956978).

Almost surely, 2^91022291 is an apocalyptic number.

91022291 is a deficient number, since it is larger than the sum of its proper divisors (805621).

91022291 is a wasteful number, since it uses less digits than its factorization.

91022291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805620.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 91022291 is about 9540.5603084934. The cubic root of 91022291 is about 449.8308681272.

The spelling of 91022291 in words is "ninety-one million, twenty-two thousand, two hundred ninety-one".