2289809 has 4 divisors (see below), whose sum is σ = 2345700. Its totient is φ = 2233920.

The previous prime is 2289803. The next prime is 2289817. The reversal of 2289809 is 9089822.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 960400 + 1329409 = 980^2 + 1153^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2289809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2289803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27884 + ... + 27965.

It is an arithmetic number, because the mean of its divisors is an integer number (586425).

2^2289809 is an apocalyptic number.

It is an amenable number.

2289809 is a deficient number, since it is larger than the sum of its proper divisors (55891).

2289809 is an equidigital number, since it uses as much as digits as its factorization.

2289809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55890.

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 2289809 is about 1513.2114855499. The cubic root of 2289809 is about 131.8053643574.

The spelling of 2289809 in words is "two million, two hundred eighty-nine thousand, eight hundred nine".