549805 has 4 divisors (see below), whose sum is σ = 659772. Its totient is φ = 439840.

The previous prime is 549767. The next prime is 549817. The reversal of 549805 is 508945.

549805 is digitally balanced in base 2, 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, and also an emirpimes, since its reverse is a distinct semiprime: 508945 = 5 ⋅101789.

It can be written as a sum of positive squares in 2 ways, for example, as 412164 + 137641 = 642^2 + 371^2 .

It is not a de Polignac number, because 549805 - 2¹³ = 541613 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54976 + ... + 54985.

It is an arithmetic number, because the mean of its divisors is an integer number (164943).

2⁵⁴⁹⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

549805 is a deficient number, since it is larger than the sum of its proper divisors (109967).

549805 is a wasteful number, since it uses less digits than its factorization.

549805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109966.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 549805 is about 741.4883680814. The cubic root of 549805 is about 81.9224430278.

The spelling of 549805 in words is "five hundred forty-nine thousand, eight hundred five".