2009831209 has 2 divisors, whose sum is σ = 2009831210. Its totient is φ = 2009831208.

The previous prime is 2009831189. The next prime is 2009831251. The reversal of 2009831209 is 9021389002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1631917609 + 377913600 = 40397^2 + 19440^2 .

It is a cyclic number.

It is not a de Polignac number, because 2009831209 - 2¹⁹ = 2009306921 is a prime.

It is not a weakly prime, because it can be changed into another prime (2009831279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1004915604 + 1004915605.

It is an arithmetic number, because the mean of its divisors is an integer number (1004915605).

Almost surely, 2^2009831209 is an apocalyptic number.

It is an amenable number.

2009831209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2009831209 is an equidigital number, since it uses as much as digits as its factorization.

2009831209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 2009831209 is about 44831.1410628817. The cubic root of 2009831209 is about 1261.9821009983.

The spelling of 2009831209 in words is "two billion, nine million, eight hundred thirty-one thousand, two hundred nine".