56809 has 2 divisors, whose sum is σ = 56810. Its totient is φ = 56808.

The previous prime is 56807. The next prime is 56813. The reversal of 56809 is 90865.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29584 + 27225 = 172^2 + 165^2 .

It is a cyclic number.

It is not a de Polignac number, because 56809 - 2¹ = 56807 is a prime.

Together with 56807, it forms a pair of twin primes.

It is a plaindrome in base 14.

It is not a weakly prime, because it can be changed into another prime (56807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28404 + 28405.

It is an arithmetic number, because the mean of its divisors is an integer number (28405).

2⁵⁶⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

56809 is a deficient number, since it is larger than the sum of its proper divisors (1).

56809 is an equidigital number, since it uses as much as digits as its factorization.

56809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 56809 is about 238.3463865889. The cubic root of 56809 is about 38.4419770272.

The spelling of 56809 in words is "fifty-six thousand, eight hundred nine".