3218209 has 2 divisors, whose sum is σ = 3218210. Its totient is φ = 3218208.

The previous prime is 3218207. The next prime is 3218221. The reversal of 3218209 is 9028123.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1617984 + 1600225 = 1272^2 + 1265^2 .

It is a cyclic number.

It is not a de Polignac number, because 3218209 - 2¹ = 3218207 is a prime.

Together with 3218207, it forms a pair of twin primes.

3218209 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (3218207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1609104 + 1609105.

It is an arithmetic number, because the mean of its divisors is an integer number (1609105).

Almost surely, 2^3218209 is an apocalyptic number.

It is an amenable number.

3218209 is a deficient number, since it is larger than the sum of its proper divisors (1).

3218209 is an equidigital number, since it uses as much as digits as its factorization.

3218209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 3218209 is about 1793.9367324407. The cubic root of 3218209 is about 147.6402419877.

The spelling of 3218209 in words is "three million, two hundred eighteen thousand, two hundred nine".