565639 has 4 divisors (see below), whose sum is σ = 590256. Its totient is φ = 541024.

The previous prime is 565637. The next prime is 565651. The reversal of 565639 is 936565.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 565639 - 2¹ = 565637 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 (565637) 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, 12274 + ... + 12319.

It is an arithmetic number, because the mean of its divisors is an integer number (147564).

2⁵⁶⁵⁶³⁹ is an apocalyptic number.

565639 is a deficient number, since it is larger than the sum of its proper divisors (24617).

565639 is a wasteful number, since it uses less digits than its factorization.

565639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24616.

The product of its digits is 24300, while the sum is 34.

The square root of 565639 is about 752.0897552819. The cubic root of 565639 is about 82.7014483219.

The spelling of 565639 in words is "five hundred sixty-five thousand, six hundred thirty-nine".