56664809 has 2 divisors, whose sum is σ = 56664810. Its totient is φ = 56664808.

The previous prime is 56664799. The next prime is 56664823. The reversal of 56664809 is 90846665.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29593600 + 27071209 = 5440^2 + 5203^2 .

It is a cyclic number.

It is not a de Polignac number, because 56664809 - 2²⁰ = 55616233 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 56664809.

It is not a weakly prime, because it can be changed into another prime (56664899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28332404 + 28332405.

It is an arithmetic number, because the mean of its divisors is an integer number (28332405).

Almost surely, 2^56664809 is an apocalyptic number.

It is an amenable number.

56664809 is a deficient number, since it is larger than the sum of its proper divisors (1).

56664809 is an equidigital number, since it uses as much as digits as its factorization.

56664809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 311040, while the sum is 44.

The square root of 56664809 is about 7527.6031377856. The cubic root of 56664809 is about 384.0942535742.

The spelling of 56664809 in words is "fifty-six million, six hundred sixty-four thousand, eight hundred nine".