56511509 has 2 divisors, whose sum is σ = 56511510. Its totient is φ = 56511508.

The previous prime is 56511493. The next prime is 56511551. The reversal of 56511509 is 90511565.

56511509 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., 39413284 + 17098225 = 6278^2 + 4135^2 .

It is a cyclic number.

It is not a de Polignac number, because 56511509 - 2⁴ = 56511493 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56511209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28255754 + 28255755.

It is an arithmetic number, because the mean of its divisors is an integer number (28255755).

Almost surely, 2^56511509 is an apocalyptic number.

It is an amenable number.

56511509 is a deficient number, since it is larger than the sum of its proper divisors (1).

56511509 is an equidigital number, since it uses as much as digits as its factorization.

56511509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6750, while the sum is 32.

The square root of 56511509 is about 7517.4137174962. The cubic root of 56511509 is about 383.7475667492.

The spelling of 56511509 in words is "fifty-six million, five hundred eleven thousand, five hundred nine".