2009549 has 4 divisors (see below), whose sum is σ = 2030364. Its totient is φ = 1988736.

The previous prime is 2009543. The next prime is 2009593. The reversal of 2009549 is 9459002.

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 366025 + 1643524 = 605^2 + 1282^2 .

It is a cyclic number.

It is not a de Polignac number, because 2009549 - 2¹² = 2005453 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 (2009543) 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 3 ways as a sum of consecutive naturals, for example, 10262 + ... + 10455.

It is an arithmetic number, because the mean of its divisors is an integer number (507591).

2^2009549 is an apocalyptic number.

It is an amenable number.

2009549 is a deficient number, since it is larger than the sum of its proper divisors (20815).

2009549 is an equidigital number, since it uses as much as digits as its factorization.

2009549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20814.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 2009549 is about 1417.5856235163. The cubic root of 2009549 is about 126.1923031465.

The spelling of 2009549 in words is "two million, nine thousand, five hundred forty-nine".