2091810809 has 16 divisors (see below), whose sum is σ = 2337470784. Its totient is φ = 1855492800.

The previous prime is 2091810797. The next prime is 2091810817. The reversal of 2091810809 is 9080181902.

It is a cyclic number.

It is not a de Polignac number, because 2091810809 - 2¹⁶ = 2091745273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2091810869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 647819 + ... + 651039.

It is an arithmetic number, because the mean of its divisors is an integer number (146091924).

Almost surely, 2^2091810809 is an apocalyptic number.

It is an amenable number.

2091810809 is a deficient number, since it is larger than the sum of its proper divisors (245659975).

2091810809 is a wasteful number, since it uses less digits than its factorization.

2091810809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4648.

The product of its (nonzero) digits is 10368, while the sum is 38.

The square root of 2091810809 is about 45736.3182711508. The cubic root of 2091810809 is about 1278.9124080645.

The spelling of 2091810809 in words is "two billion, ninety-one million, eight hundred ten thousand, eight hundred nine".