509318985689 has 2 divisors, whose sum is σ = 509318985690. Its totient is φ = 509318985688.

The previous prime is 509318985683. The next prime is 509318985691. The reversal of 509318985689 is 986589813905.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 382037720464 + 127281265225 = 618092^2 + 356765^2 .

It is a cyclic number.

It is not a de Polignac number, because 509318985689 - 2⁴ = 509318985673 is a prime.

Together with 509318985691, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (509318985683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254659492844 + 254659492845.

It is an arithmetic number, because the mean of its divisors is an integer number (254659492845).

Almost surely, 2^509318985689 is an apocalyptic number.

It is an amenable number.

509318985689 is a deficient number, since it is larger than the sum of its proper divisors (1).

509318985689 is an equidigital number, since it uses as much as digits as its factorization.

509318985689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 167961600, while the sum is 71.

The spelling of 509318985689 in words is "five hundred nine billion, three hundred eighteen million, nine hundred eighty-five thousand, six hundred eighty-nine".