549386721 has 27 divisors (see below), whose sum is σ = 860729337. Its totient is φ = 337521600.

The previous prime is 549386699. The next prime is 549386731. The reversal of 549386721 is 127683945.

The square root of 549386721 is 23439.

It is a perfect power (a square), and thus also a powerful number.

549386721 is a `hidden beast` number, since 549 + 3 + 86 + 7 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 140625 + 549246096 = 375^2 + 23436^2 .

It is a de Polignac number, because none of the positive numbers 2^k-549386721 is a prime.

It is a super-2 number, since 2×549386721² = 603651538422263682, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (549386731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 913821 + ... + 914421.

Almost surely, 2^549386721 is an apocalyptic number.

549386721 is the 23439-th square number.

549386721 is the 11720-th centered octagonal number.

It is an amenable number.

549386721 is a deficient number, since it is larger than the sum of its proper divisors (311342616).

549386721 is an equidigital number, since it uses as much as digits as its factorization.

549386721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1234 (or 617 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The cubic root of 549386721 is about 819.0166285362.

The spelling of 549386721 in words is "five hundred forty-nine million, three hundred eighty-six thousand, seven hundred twenty-one".