11221209 has 12 divisors (see below), whose sum is σ = 16391700. Its totient is φ = 7396224.

The previous prime is 11221193. The next prime is 11221211. The reversal of 11221209 is 90212211.

11221209 = T₄₅₇ + T₄₅₈ + ... + T₅₄₅.

It can be written as a sum of positive squares in 2 ways, for example, as 5475600 + 5745609 = 2340^2 + 2397^2 .

It is not a de Polignac number, because 11221209 - 2⁴ = 11221193 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11221191 and 11221200.

It is not an unprimeable number, because it can be changed into a prime (11221219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6204 + ... + 7805.

It is an arithmetic number, because the mean of its divisors is an integer number (1365975).

Almost surely, 2^11221209 is an apocalyptic number.

It is an amenable number.

11221209 is a deficient number, since it is larger than the sum of its proper divisors (5170491).

11221209 is a wasteful number, since it uses less digits than its factorization.

11221209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14104 (or 14101 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 11221209 is about 3349.8073078910. The cubic root of 11221209 is about 223.8789271842.

It can be divided in two parts, 112 and 21209, that added together give a triangular number (21321 = T₂₀₆).

The spelling of 11221209 in words is "eleven million, two hundred twenty-one thousand, two hundred nine".