540805 has 4 divisors (see below), whose sum is σ = 648972. Its totient is φ = 432640.

The previous prime is 540803. The next prime is 540809. The reversal of 540805 is 508045.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 311364 + 229441 = 558^2 + 479^2 .

It is not a de Polignac number, because 540805 - 2¹ = 540803 is a prime.

It is a Smith number, since the sum of its digits (22) 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 not an unprimeable number, because it can be changed into a prime (540803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54076 + ... + 54085.

It is an arithmetic number, because the mean of its divisors is an integer number (162243).

2⁵⁴⁰⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

540805 is a deficient number, since it is larger than the sum of its proper divisors (108167).

540805 is a wasteful number, since it uses less digits than its factorization.

540805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108166.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 540805 is about 735.3944519780. The cubic root of 540805 is about 81.4729733362.

It can be divided in two parts, 54080 and 5, that multiplied together give a square (270400 = 520²).

The spelling of 540805 in words is "five hundred forty thousand, eight hundred five".