522721 has 4 divisors (see below), whose sum is σ = 545472. Its totient is φ = 499972.

The previous prime is 522719. The next prime is 522737. The reversal of 522721 is 127225.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 522721 - 2¹ = 522719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (522761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11341 + ... + 11386.

It is an arithmetic number, because the mean of its divisors is an integer number (136368).

2⁵²²⁷²¹ is an apocalyptic number.

It is an amenable number.

522721 is a deficient number, since it is larger than the sum of its proper divisors (22751).

522721 is a wasteful number, since it uses less digits than its factorization.

522721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22750.

The product of its digits is 280, while the sum is 19.

The square root of 522721 is about 722.9944674754. The cubic root of 522721 is about 80.5545327038.

Adding to 522721 its reverse (127225), we get a palindrome (649946).

The spelling of 522721 in words is "five hundred twenty-two thousand, seven hundred twenty-one".