65783945809 has 2 divisors, whose sum is σ = 65783945810. Its totient is φ = 65783945808.

The previous prime is 65783945771. The next prime is 65783945827. The reversal of 65783945809 is 90854938756.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42082419600 + 23701526209 = 205140^2 + 153953^2 .

It is a cyclic number.

It is not a de Polignac number, because 65783945809 - 2⁷ = 65783945681 is a prime.

It is not a weakly prime, because it can be changed into another prime (65783945849) 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, 32891972904 + 32891972905.

It is an arithmetic number, because the mean of its divisors is an integer number (32891972905).

Almost surely, 2^65783945809 is an apocalyptic number.

It is an amenable number.

65783945809 is a deficient number, since it is larger than the sum of its proper divisors (1).

65783945809 is an equidigital number, since it uses as much as digits as its factorization.

65783945809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 65318400, while the sum is 64.

The spelling of 65783945809 in words is "sixty-five billion, seven hundred eighty-three million, nine hundred forty-five thousand, eight hundred nine".