2118217 has 4 divisors (see below), whose sum is σ = 2242836. Its totient is φ = 1993600.

The previous prime is 2118209. The next prime is 2118239. The reversal of 2118217 is 7128112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1279161 + 839056 = 1131^2 + 916^2 .

It is a cyclic number.

It is not a de Polignac number, because 2118217 - 2³ = 2118209 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2118517) 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 3 ways as a sum of consecutive naturals, for example, 62284 + ... + 62317.

It is an arithmetic number, because the mean of its divisors is an integer number (560709).

2^2118217 is an apocalyptic number.

It is an amenable number.

2118217 is a deficient number, since it is larger than the sum of its proper divisors (124619).

2118217 is a wasteful number, since it uses less digits than its factorization.

2118217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124618.

The product of its digits is 224, while the sum is 22.

The square root of 2118217 is about 1455.4095643495. The cubic root of 2118217 is about 128.4271415468.

The spelling of 2118217 in words is "two million, one hundred eighteen thousand, two hundred seventeen".