2107809 has 32 divisors (see below), whose sum is σ = 3502080. Its totient is φ = 1242000.

The previous prime is 2107771. The next prime is 2107811. The reversal of 2107809 is 9087012.

It is not a de Polignac number, because 2107809 - 2¹² = 2103713 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2107849) 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 31 ways as a sum of consecutive naturals, for example, 13884 + ... + 14034.

It is an arithmetic number, because the mean of its divisors is an integer number (109440).

2^2107809 is an apocalyptic number.

It is an amenable number.

2107809 is a deficient number, since it is larger than the sum of its proper divisors (1394271).

2107809 is a wasteful number, since it uses less digits than its factorization.

2107809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218 (or 212 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 2107809 is about 1451.8295354483. The cubic root of 2107809 is about 128.2164509901.

It can be divided in two parts, 2107 and 809, that added together give a square (2916 = 54²).

The spelling of 2107809 in words is "two million, one hundred seven thousand, eight hundred nine".