2105405 has 4 divisors (see below), whose sum is σ = 2526492. Its totient is φ = 1684320.

The previous prime is 2105381. The next prime is 2105407. The reversal of 2105405 is 5045012.

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 755161 + 1350244 = 869^2 + 1162^2 .

It is not a de Polignac number, because 2105405 - 2⁸ = 2105149 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 (2105407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210536 + ... + 210545.

It is an arithmetic number, because the mean of its divisors is an integer number (631623).

2^2105405 is an apocalyptic number.

It is an amenable number.

2105405 is a deficient number, since it is larger than the sum of its proper divisors (421087).

2105405 is an equidigital number, since it uses as much as digits as its factorization.

2105405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 421086.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 2105405 is about 1451.0013783591. The cubic root of 2105405 is about 128.1676879373.

The spelling of 2105405 in words is "two million, one hundred five thousand, four hundred five".