565820 has 24 divisors (see below), whose sum is σ = 1251600. Its totient is φ = 214272.

The previous prime is 565813. The next prime is 565849. The reversal of 565820 is 28565.

It is a self number, because there is not a number n which added to its sum of digits gives 565820.

It is a congruent number.

It is an unprimeable number.

565820 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 365 + ... + 1124.

It is an arithmetic number, because the mean of its divisors is an integer number (52150).

2⁵⁶⁵⁸²⁰ is an apocalyptic number.

It is an amenable number.

565820 is an abundant number, since it is smaller than the sum of its proper divisors (685780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

565820 is a wasteful number, since it uses less digits than its factorization.

565820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1517 (or 1515 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 565820 is about 752.2100770397. The cubic root of 565820 is about 82.7102686506.

The spelling of 565820 in words is "five hundred sixty-five thousand, eight hundred twenty".