2216809 has 16 divisors (see below), whose sum is σ = 2707200. Its totient is φ = 1811040.

The previous prime is 2216803. The next prime is 2216821. The reversal of 2216809 is 9086122.

It is a happy number.

2216809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2216809 - 2⁵ = 2216777 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2216803) 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 in 15 ways as a sum of consecutive naturals, for example, 7749 + ... + 8029.

It is an arithmetic number, because the mean of its divisors is an integer number (169200).

2^2216809 is an apocalyptic number.

It is an amenable number.

2216809 is a deficient number, since it is larger than the sum of its proper divisors (490391).

2216809 is an equidigital number, since it uses as much as digits as its factorization.

2216809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325 (or 311 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 2216809 is about 1488.8952280130. The cubic root of 2216809 is about 130.3895416418.

It can be divided in two parts, 2216 and 809, that added together give a square (3025 = 55²).

The spelling of 2216809 in words is "two million, two hundred sixteen thousand, eight hundred nine".