2005909 has 4 divisors (see below), whose sum is σ = 2020480. Its totient is φ = 1991340.

The previous prime is 2005903. The next prime is 2005919. The reversal of 2005909 is 9095002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2005909 - 2⁵ = 2005877 is a prime.

It is a Duffinian number.

2005909 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2005903) 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, 7077 + ... + 7354.

It is an arithmetic number, because the mean of its divisors is an integer number (505120).

2^2005909 is an apocalyptic number.

It is an amenable number.

2005909 is a deficient number, since it is larger than the sum of its proper divisors (14571).

2005909 is a wasteful number, since it uses less digits than its factorization.

2005909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14570.

The product of its (nonzero) digits is 810, while the sum is 25.

The square root of 2005909 is about 1416.3011685373. The cubic root of 2005909 is about 126.1160642151.

The spelling of 2005909 in words is "two million, five thousand, nine hundred nine".