8549721 has 24 divisors (see below), whose sum is σ = 13044096. Its totient is φ = 5385600.

The previous prime is 8549719. The next prime is 8549773. The reversal of 8549721 is 1279458.

It is not a de Polignac number, because 8549721 - 2¹ = 8549719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (8549711) 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 23 ways as a sum of consecutive naturals, for example, 21121 + ... + 21521.

It is an arithmetic number, because the mean of its divisors is an integer number (543504).

Almost surely, 2^8549721 is an apocalyptic number.

It is an amenable number.

8549721 is a deficient number, since it is larger than the sum of its proper divisors (4494375).

8549721 is a wasteful number, since it uses less digits than its factorization.

8549721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533 (or 530 counting only the distinct ones).

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

The square root of 8549721 is about 2923.9905950601. The cubic root of 8549721 is about 204.4799110672.

The spelling of 8549721 in words is "eight million, five hundred forty-nine thousand, seven hundred twenty-one".