2231209 has 2 divisors, whose sum is σ = 2231210. Its totient is φ = 2231208.

The previous prime is 2231171. The next prime is 2231219. The reversal of 2231209 is 9021322.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2073600 + 157609 = 1440^2 + 397^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2231209 is a prime.

It is a super-3 number, since 3×2231209³ = 33322840466139186987, which contains 333 as substring.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (2231219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1115604 + 1115605.

It is an arithmetic number, because the mean of its divisors is an integer number (1115605).

2^2231209 is an apocalyptic number.

It is an amenable number.

2231209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2231209 is an equidigital number, since it uses as much as digits as its factorization.

2231209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 2231209 is about 1493.7232005964. The cubic root of 2231209 is about 130.6712616680.

The spelling of 2231209 in words is "two million, two hundred thirty-one thousand, two hundred nine".