2118805 has 16 divisors (see below), whose sum is σ = 2815344. Its totient is φ = 1520640.

The previous prime is 2118803. The next prime is 2118811. The reversal of 2118805 is 5088112.

It can be written as a sum of positive squares in 8 ways, for example, as 96721 + 2022084 = 311^2 + 1422^2 .

It is not a de Polignac number, because 2118805 - 2¹ = 2118803 is a prime.

It is a Duffinian number.

2118805 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 2118805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2118803) 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, 1965 + ... + 2845.

It is an arithmetic number, because the mean of its divisors is an integer number (175959).

2^2118805 is an apocalyptic number.

It is an amenable number.

2118805 is a deficient number, since it is larger than the sum of its proper divisors (696539).

2118805 is a wasteful number, since it uses less digits than its factorization.

2118805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 936.

The product of its (nonzero) digits is 640, while the sum is 25.

The square root of 2118805 is about 1455.6115553265. The cubic root of 2118805 is about 128.4390238945.

The spelling of 2118805 in words is "two million, one hundred eighteen thousand, eight hundred five".