218668500 has 72 divisors (see below), whose sum is σ = 689840424. Its totient is φ = 58310400.

The previous prime is 218668493. The next prime is 218668523. The reversal of 218668500 is 5866812.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5391684 + 213276816 = 2322^2 + 14604^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 in 23 ways as a sum of consecutive naturals, for example, 19797 + ... + 28796.

It is an arithmetic number, because the mean of its divisors is an integer number (9581117).

Almost surely, 2^218668500 is an apocalyptic number.

218668500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

218668500 is an abundant number, since it is smaller than the sum of its proper divisors (471171924).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

218668500 is a wasteful number, since it uses less digits than its factorization.

218668500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48618 (or 48603 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 218668500 is about 14787.4439982033. The cubic root of 218668500 is about 602.4607275699.

The spelling of 218668500 in words is "two hundred eighteen million, six hundred sixty-eight thousand, five hundred".