2840209 has 2 divisors, whose sum is σ = 2840210. Its totient is φ = 2840208.

The previous prime is 2840203. The next prime is 2840237. The reversal of 2840209 is 9020482.

2840209 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., 2039184 + 801025 = 1428^2 + 895^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2840209 is a prime.

It is not a weakly prime, because it can be changed into another prime (2840203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1420104 + 1420105.

It is an arithmetic number, because the mean of its divisors is an integer number (1420105).

2^2840209 is an apocalyptic number.

It is an amenable number.

2840209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2840209 is an equidigital number, since it uses as much as digits as its factorization.

2840209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 2840209 is about 1685.2919628361. The cubic root of 2840209 is about 141.6174488004.

The spelling of 2840209 in words is "two million, eight hundred forty thousand, two hundred nine".