2109905 has 16 divisors (see below), whose sum is σ = 3020544. Its totient is φ = 1383360.

The previous prime is 2109889. The next prime is 2109911. The reversal of 2109905 is 5099012.

It is a happy number.

It is not a de Polignac number, because 2109905 - 2⁴ = 2109889 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 506 + ... + 2115.

It is an arithmetic number, because the mean of its divisors is an integer number (188784).

2^2109905 is an apocalyptic number.

It is an amenable number.

2109905 is a deficient number, since it is larger than the sum of its proper divisors (910639).

2109905 is a wasteful number, since it uses less digits than its factorization.

2109905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2656.

The product of its (nonzero) digits is 810, while the sum is 26.

The square root of 2109905 is about 1452.5512039168. The cubic root of 2109905 is about 128.2589362835.

The spelling of 2109905 in words is "two million, one hundred nine thousand, nine hundred five".