540521 has 4 divisors (see below), whose sum is σ = 549444. Its totient is φ = 531600.

The previous prime is 540517. The next prime is 540539. The reversal of 540521 is 125045.

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 290521 + 250000 = 539^2 + 500^2 .

It is a cyclic number.

It is not a de Polignac number, because 540521 - 2² = 540517 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 540521.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 540521.

It is not an unprimeable number, because it can be changed into a prime (540511) 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 3 ways as a sum of consecutive naturals, for example, 4370 + ... + 4491.

It is an arithmetic number, because the mean of its divisors is an integer number (137361).

2⁵⁴⁰⁵²¹ is an apocalyptic number.

It is an amenable number.

540521 is a deficient number, since it is larger than the sum of its proper divisors (8923).

540521 is an equidigital number, since it uses as much as digits as its factorization.

540521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8922.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 540521 is about 735.2013329694. The cubic root of 540521 is about 81.4587091831.

Adding to 540521 its reverse (125045), we get a palindrome (665566).

The spelling of 540521 in words is "five hundred forty thousand, five hundred twenty-one".