7218549 has 24 divisors (see below), whose sum is σ = 11356800. Its totient is φ = 4391712.

The previous prime is 7218529. The next prime is 7218551. The reversal of 7218549 is 9458127.

It is not a de Polignac number, because 7218549 - 2²⁰ = 6169973 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7218529) 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 23 ways as a sum of consecutive naturals, for example, 11752 + ... + 12350.

It is an arithmetic number, because the mean of its divisors is an integer number (473200).

Almost surely, 2^7218549 is an apocalyptic number.

It is an amenable number.

7218549 is a deficient number, since it is larger than the sum of its proper divisors (4138251).

7218549 is a wasteful number, since it uses less digits than its factorization.

7218549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 721 (or 718 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 7218549 is about 2686.7357517999. The cubic root of 7218549 is about 193.2635575261.

The spelling of 7218549 in words is "seven million, two hundred eighteen thousand, five hundred forty-nine".