9021991 has 8 divisors (see below), whose sum is σ = 9882000. Its totient is φ = 8168640.

The previous prime is 9021977. The next prime is 9022001. The reversal of 9021991 is 1991209.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9021991 - 2⁷ = 9021863 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 (9021931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1435 + ... + 4483.

It is an arithmetic number, because the mean of its divisors is an integer number (1235250).

Almost surely, 2^9021991 is an apocalyptic number.

9021991 is a deficient number, since it is larger than the sum of its proper divisors (860009).

9021991 is a wasteful number, since it uses less digits than its factorization.

9021991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3329.

The product of its (nonzero) digits is 1458, while the sum is 31.

The square root of 9021991 is about 3003.6629304900. The cubic root of 9021991 is about 208.1776634790.

The spelling of 9021991 in words is "nine million, twenty-one thousand, nine hundred ninety-one".