218668 has 6 divisors (see below), whose sum is σ = 382676. Its totient is φ = 109332.

The previous prime is 218657. The next prime is 218677. The reversal of 218668 is 866812.

218668 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 15.

It is a nialpdrome in base 12.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27330 + ... + 27337.

2²¹⁸⁶⁶⁸ is an apocalyptic number.

It is an amenable number.

218668 is a deficient number, since it is larger than the sum of its proper divisors (164008).

218668 is a wasteful number, since it uses less digits than its factorization.

218668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54671 (or 54669 counting only the distinct ones).

The product of its digits is 4608, while the sum is 31.

The square root of 218668 is about 467.6195034427. The cubic root of 218668 is about 60.2460268381.

The spelling of 218668 in words is "two hundred eighteen thousand, six hundred sixty-eight".