568661 has 4 divisors (see below), whose sum is σ = 588300. Its totient is φ = 549024.

The previous prime is 568657. The next prime is 568669. The reversal of 568661 is 166865.

568661 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.

It can be written as a sum of positive squares in 2 ways, for example, as 481636 + 87025 = 694^2 + 295^2 .

It is a cyclic number.

It is not a de Polignac number, because 568661 - 2² = 568657 is a prime.

It is an Ulam 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 (568669) 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, 9776 + ... + 9833.

It is an arithmetic number, because the mean of its divisors is an integer number (147075).

2⁵⁶⁸⁶⁶¹ is an apocalyptic number.

It is an amenable number.

568661 is a deficient number, since it is larger than the sum of its proper divisors (19639).

568661 is a wasteful number, since it uses less digits than its factorization.

568661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19638.

The product of its digits is 8640, while the sum is 32.

The square root of 568661 is about 754.0961477159. The cubic root of 568661 is about 82.8484678931.

The spelling of 568661 in words is "five hundred sixty-eight thousand, six hundred sixty-one".