218265191 has 2 divisors, whose sum is σ = 218265192. Its totient is φ = 218265190.

The previous prime is 218265169. The next prime is 218265209. The reversal of 218265191 is 191562812.

218265191 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 218265191 - 2¹⁸ = 218003047 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218265161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109132595 + 109132596.

It is an arithmetic number, because the mean of its divisors is an integer number (109132596).

Almost surely, 2^218265191 is an apocalyptic number.

218265191 is a deficient number, since it is larger than the sum of its proper divisors (1).

218265191 is an equidigital number, since it uses as much as digits as its factorization.

218265191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 35.

The square root of 218265191 is about 14773.8008312012. The cubic root of 218265191 is about 602.0901096888.

The spelling of 218265191 in words is "two hundred eighteen million, two hundred sixty-five thousand, one hundred ninety-one".