218384189 has 2 divisors, whose sum is σ = 218384190. Its totient is φ = 218384188.

The previous prime is 218384183. The next prime is 218384191. The reversal of 218384189 is 981483812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200448964 + 17935225 = 14158^2 + 4235^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-218384189 is a prime.

Together with 218384191, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218384183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109192094 + 109192095.

It is an arithmetic number, because the mean of its divisors is an integer number (109192095).

Almost surely, 2^218384189 is an apocalyptic number.

It is an amenable number.

218384189 is a deficient number, since it is larger than the sum of its proper divisors (1).

218384189 is an equidigital number, since it uses as much as digits as its factorization.

218384189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 110592, while the sum is 44.

The square root of 218384189 is about 14777.8276143688. The cubic root of 218384189 is about 602.1995094848.

The spelling of 218384189 in words is "two hundred eighteen million, three hundred eighty-four thousand, one hundred eighty-nine".