985547209 has 2 divisors, whose sum is σ = 985547210. Its totient is φ = 985547208.

The previous prime is 985547201. The next prime is 985547219. The reversal of 985547209 is 902745589.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 836829184 + 148718025 = 28928^2 + 12195^2 .

It is an emirp because it is prime and its reverse (902745589) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 985547209 - 2³ = 985547201 is a prime.

It is not a weakly prime, because it can be changed into another prime (985547201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 492773604 + 492773605.

It is an arithmetic number, because the mean of its divisors is an integer number (492773605).

Almost surely, 2^985547209 is an apocalyptic number.

It is an amenable number.

985547209 is a deficient number, since it is larger than the sum of its proper divisors (1).

985547209 is an equidigital number, since it uses as much as digits as its factorization.

985547209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 907200, while the sum is 49.

The square root of 985547209 is about 31393.4262067714. The cubic root of 985547209 is about 995.1590055897.

The spelling of 985547209 in words is "nine hundred eighty-five million, five hundred forty-seven thousand, two hundred nine".