218189 has 4 divisors (see below), whose sum is σ = 224124. Its totient is φ = 212256.

The previous prime is 218171. The next prime is 218191. The reversal of 218189 is 981812.

218189 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 198025 + 20164 = 445^2 + 142^2 .

It is a cyclic number.

It is not a de Polignac number, because 218189 - 2⁸ = 217933 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218149) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2912 + ... + 2985.

It is an arithmetic number, because the mean of its divisors is an integer number (56031).

2²¹⁸¹⁸⁹ is an apocalyptic number.

It is an amenable number.

218189 is a deficient number, since it is larger than the sum of its proper divisors (5935).

218189 is an equidigital number, since it uses as much as digits as its factorization.

218189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5934.

The product of its digits is 1152, while the sum is 29.

The square root of 218189 is about 467.1070541107. The cubic root of 218189 is about 60.2020043262.

The spelling of 218189 in words is "two hundred eighteen thousand, one hundred eighty-nine".