218168213 has 2 divisors, whose sum is σ = 218168214. Its totient is φ = 218168212.

The previous prime is 218168207. The next prime is 218168261. The reversal of 218168213 is 312861812.

218168213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 212518084 + 5650129 = 14578^2 + 2377^2 .

It is a cyclic number.

It is not a de Polignac number, because 218168213 - 2⁶ = 218168149 is a prime.

It is a super-2 number, since 2×218168213² = 95194738327226738, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 218168213.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218168263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109084106 + 109084107.

It is an arithmetic number, because the mean of its divisors is an integer number (109084107).

Almost surely, 2^218168213 is an apocalyptic number.

It is an amenable number.

218168213 is a deficient number, since it is larger than the sum of its proper divisors (1).

218168213 is an equidigital number, since it uses as much as digits as its factorization.

218168213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 32.

The square root of 218168213 is about 14770.5183727586. The cubic root of 218168213 is about 602.0009243813. Note that the first 3 decimals are identical.

The spelling of 218168213 in words is "two hundred eighteen million, one hundred sixty-eight thousand, two hundred thirteen".