56518909 has 2 divisors, whose sum is σ = 56518910. Its totient is φ = 56518908.

The previous prime is 56518867. The next prime is 56518919. The reversal of 56518909 is 90981565.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51523684 + 4995225 = 7178^2 + 2235^2 .

It is a cyclic number.

It is not a de Polignac number, because 56518909 - 2¹³ = 56510717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56518919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28259454 + 28259455.

It is an arithmetic number, because the mean of its divisors is an integer number (28259455).

Almost surely, 2^56518909 is an apocalyptic number.

It is an amenable number.

56518909 is a deficient number, since it is larger than the sum of its proper divisors (1).

56518909 is an equidigital number, since it uses as much as digits as its factorization.

56518909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 97200, while the sum is 43.

The square root of 56518909 is about 7517.9058919356. The cubic root of 56518909 is about 383.7643161872.

The spelling of 56518909 in words is "fifty-six million, five hundred eighteen thousand, nine hundred nine".