985688309 has 2 divisors, whose sum is σ = 985688310. Its totient is φ = 985688308.

The previous prime is 985688273. The next prime is 985688351. The reversal of 985688309 is 903886589.

985688309 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., 836482084 + 149206225 = 28922^2 + 12215^2 .

It is a cyclic number.

It is not a de Polignac number, because 985688309 - 2²⁴ = 968911093 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (985688009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 492844154 + 492844155.

It is an arithmetic number, because the mean of its divisors is an integer number (492844155).

Almost surely, 2^985688309 is an apocalyptic number.

It is an amenable number.

985688309 is a deficient number, since it is larger than the sum of its proper divisors (1).

985688309 is an equidigital number, since it uses as much as digits as its factorization.

985688309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3732480, while the sum is 56.

The square root of 985688309 is about 31395.6734121121. The cubic root of 985688309 is about 995.2064953612.

The spelling of 985688309 in words is "nine hundred eighty-five million, six hundred eighty-eight thousand, three hundred nine".