561823 has 8 divisors (see below), whose sum is σ = 586656. Its totient is φ = 537600.

The previous prime is 561809. The next prime is 561829. The reversal of 561823 is 328165.

It is a happy number.

561823 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 561823 - 2¹⁷ = 430751 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 (561829) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2815 + ... + 3007.

It is an arithmetic number, because the mean of its divisors is an integer number (73332).

2⁵⁶¹⁸²³ is an apocalyptic number.

561823 is a deficient number, since it is larger than the sum of its proper divisors (24833).

561823 is a wasteful number, since it uses less digits than its factorization.

561823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305.

The product of its digits is 1440, while the sum is 25.

The square root of 561823 is about 749.5485307837. The cubic root of 561823 is about 82.5150508200.

Adding to 561823 its reverse (328165), we get a palindrome (889988).

The spelling of 561823 in words is "five hundred sixty-one thousand, eight hundred twenty-three".