2090905 has 4 divisors (see below), whose sum is σ = 2509092. Its totient is φ = 1672720.

The previous prime is 2090873. The next prime is 2090923. The reversal of 2090905 is 5090902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5090902 = 2 ⋅2545451.

It can be written as a sum of positive squares in 2 ways, for example, as 1175056 + 915849 = 1084^2 + 957^2 .

It is not a de Polignac number, because 2090905 - 2⁵ = 2090873 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 2090905.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209086 + ... + 209095.

It is an arithmetic number, because the mean of its divisors is an integer number (627273).

2^2090905 is an apocalyptic number.

It is an amenable number.

2090905 is a deficient number, since it is larger than the sum of its proper divisors (418187).

2090905 is an equidigital number, since it uses as much as digits as its factorization.

2090905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418186.

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

The square root of 2090905 is about 1445.9961963989. The cubic root of 2090905 is about 127.8727780529.

The spelling of 2090905 in words is "two million, ninety thousand, nine hundred five".