564561221 has 16 divisors (see below), whose sum is σ = 654407424. Its totient is φ = 477060864.

The previous prime is 564561203. The next prime is 564561251. The reversal of 564561221 is 122165465.

It is a de Polignac number, because none of the positive numbers 2^k-564561221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (564561251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 154016 + ... + 157638.

It is an arithmetic number, because the mean of its divisors is an integer number (40900464).

Almost surely, 2^564561221 is an apocalyptic number.

It is an amenable number.

564561221 is a deficient number, since it is larger than the sum of its proper divisors (89846203).

564561221 is a wasteful number, since it uses less digits than its factorization.

564561221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3940.

The product of its digits is 14400, while the sum is 32.

The square root of 564561221 is about 23760.4970697164. The cubic root of 564561221 is about 826.4888796874.

It can be divided in two parts, 5645 and 61221, that added together give a palindrome (66866).

The spelling of 564561221 in words is "five hundred sixty-four million, five hundred sixty-one thousand, two hundred twenty-one".