566221 has 4 divisors (see below), whose sum is σ = 570492. Its totient is φ = 561952.

The previous prime is 566213. The next prime is 566227. The reversal of 566221 is 122665.

566221 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: 122665 = 5 ⋅24533.

It can be written as a sum of positive squares in 2 ways, for example, as 376996 + 189225 = 614^2 + 435^2 .

It is a cyclic number.

It is not a de Polignac number, because 566221 - 2³ = 566213 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 junction number, because it is equal to n+sod(n) for n = 566192 and 566201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (566227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1930 + ... + 2203.

It is an arithmetic number, because the mean of its divisors is an integer number (142623).

2⁵⁶⁶²²¹ is an apocalyptic number.

It is an amenable number.

566221 is a deficient number, since it is larger than the sum of its proper divisors (4271).

566221 is a wasteful number, since it uses less digits than its factorization.

566221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4270.

The product of its digits is 720, while the sum is 22.

The square root of 566221 is about 752.4765777086. The cubic root of 566221 is about 82.7298031231.

Adding to 566221 its reverse (122665), we get a palindrome (688886).

Subtracting from 566221 its reverse (122665), we obtain a square (443556 = 666²).

It can be divided in two parts, 566 and 221, that added together give a palindrome (787).

The spelling of 566221 in words is "five hundred sixty-six thousand, two hundred twenty-one".