218180218 has 4 divisors (see below), whose sum is σ = 327270330. Its totient is φ = 109090108.

The previous prime is 218180213. The next prime is 218180219. The reversal of 218180218 is 812081812.

It is a happy number.

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., 182979729 + 35200489 = 13527^2 + 5933^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 218180218.

It is not an unprimeable number, because it can be changed into a prime (218180213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54545053 + ... + 54545056.

Almost surely, 2^218180218 is an apocalyptic number.

218180218 is a deficient number, since it is larger than the sum of its proper divisors (109090112).

218180218 is a wasteful number, since it uses less digits than its factorization.

218180218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109090111.

The product of its (nonzero) digits is 2048, while the sum is 31.

The square root of 218180218 is about 14770.9247510100. The cubic root of 218180218 is about 602.0119661496.

The spelling of 218180218 in words is "two hundred eighteen million, one hundred eighty thousand, two hundred eighteen".