7221491 has 4 divisors (see below), whose sum is σ = 7285512. Its totient is φ = 7157472.

The previous prime is 7221457. The next prime is 7221499. The reversal of 7221491 is 1941227.

7221491 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 7221491 - 2²² = 3027187 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 7221491.

It is not an unprimeable number, because it can be changed into a prime (7221499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31841 + ... + 32066.

It is an arithmetic number, because the mean of its divisors is an integer number (1821378).

Almost surely, 2^7221491 is an apocalyptic number.

7221491 is a deficient number, since it is larger than the sum of its proper divisors (64021).

7221491 is a wasteful number, since it uses less digits than its factorization.

7221491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64020.

The product of its digits is 1008, while the sum is 26.

The square root of 7221491 is about 2687.2832005578. The cubic root of 7221491 is about 193.2898095314.

The spelling of 7221491 in words is "seven million, two hundred twenty-one thousand, four hundred ninety-one".