2005811 has 8 divisors (see below), whose sum is σ = 2125200. Its totient is φ = 1887840.

The previous prime is 2005799. The next prime is 2005831. The reversal of 2005811 is 1185002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2005811 - 2⁶ = 2005747 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2005811.

It is not an unprimeable number, because it can be changed into a prime (2005831) 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 7 ways as a sum of consecutive naturals, for example, 4121 + ... + 4581.

It is an arithmetic number, because the mean of its divisors is an integer number (265650).

2^2005811 is an apocalyptic number.

2005811 is a deficient number, since it is larger than the sum of its proper divisors (119389).

2005811 is a wasteful number, since it uses less digits than its factorization.

2005811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 2005811 is about 1416.2665709534. The cubic root of 2005811 is about 126.1140103539.

The spelling of 2005811 in words is "two million, five thousand, eight hundred eleven".