563821 has 2 divisors, whose sum is σ = 563822. Its totient is φ = 563820.

The previous prime is 563813. The next prime is 563831. The reversal of 563821 is 128365.

It is a happy number.

563821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 448900 + 114921 = 670^2 + 339^2 .

It is a cyclic number.

It is not a de Polignac number, because 563821 - 2³ = 563813 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (563831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 281910 + 281911.

It is an arithmetic number, because the mean of its divisors is an integer number (281911).

2⁵⁶³⁸²¹ is an apocalyptic number.

It is an amenable number.

563821 is a deficient number, since it is larger than the sum of its proper divisors (1).

563821 is an equidigital number, since it uses as much as digits as its factorization.

563821 is an evil number, because the sum of its binary digits is even.

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

The square root of 563821 is about 750.8801502237. The cubic root of 563821 is about 82.6127506420.

The spelling of 563821 in words is "five hundred sixty-three thousand, eight hundred twenty-one".