549021 has 16 divisors (see below), whose sum is σ = 811008. Its totient is φ = 327600.

The previous prime is 549019. The next prime is 549023. The reversal of 549021 is 120945.

It is an interprime number because it is at equal distance from previous prime (549019) and next prime (549023).

It is not a de Polignac number, because 549021 - 2¹ = 549019 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 549021.

It is not an unprimeable number, because it can be changed into a prime (549023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4126 + ... + 4256.

It is an arithmetic number, because the mean of its divisors is an integer number (50688).

2⁵⁴⁹⁰²¹ is an apocalyptic number.

It is an amenable number.

549021 is a deficient number, since it is larger than the sum of its proper divisors (261987).

549021 is a wasteful number, since it uses less digits than its factorization.

549021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 549021 is about 740.9595130640. The cubic root of 549021 is about 81.8834851257.

Adding to 549021 its reverse (120945), we get a palindrome (669966).

The spelling of 549021 in words is "five hundred forty-nine thousand, twenty-one".