128218 has 4 divisors (see below), whose sum is σ = 192330. Its totient is φ = 64108.

The previous prime is 128213. The next prime is 128221. The reversal of 128218 is 812821.

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

It can be written as a sum of positive squares in only one way, i.e., 69169 + 59049 = 263^2 + 243^2 .

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 not an unprimeable number, because it can be changed into a prime (128213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32053 + ... + 32056.

2¹²⁸²¹⁸ is an apocalyptic number.

128218 is a deficient number, since it is larger than the sum of its proper divisors (64112).

128218 is an equidigital number, since it uses as much as digits as its factorization.

128218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64111.

The product of its digits is 256, while the sum is 22.

The square root of 128218 is about 358.0754110519. The cubic root of 128218 is about 50.4254364758.

The spelling of 128218 in words is "one hundred twenty-eight thousand, two hundred eighteen".