2105643909 has 16 divisors (see below), whose sum is σ = 2874240512. Its totient is φ = 1370437488.

The previous prime is 2105643889. The next prime is 2105643913. The reversal of 2105643909 is 9093465012.

It is not a de Polignac number, because 2105643909 - 2¹⁷ = 2105512837 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 (2105643809) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 494142 + ... + 498384.

It is an arithmetic number, because the mean of its divisors is an integer number (179640032).

Almost surely, 2^2105643909 is an apocalyptic number.

It is an amenable number.

2105643909 is a deficient number, since it is larger than the sum of its proper divisors (768596603).

2105643909 is a wasteful number, since it uses less digits than its factorization.

2105643909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8136.

The product of its (nonzero) digits is 58320, while the sum is 39.

The square root of 2105643909 is about 45887.2957255056. The cubic root of 2105643909 is about 1281.7253565957.

The spelling of 2105643909 in words is "two billion, one hundred five million, six hundred forty-three thousand, nine hundred nine".