218214664 has 8 divisors (see below), whose sum is σ = 409152510. Its totient is φ = 109107328.

The previous prime is 218214653. The next prime is 218214707. The reversal of 218214664 is 466412812.

It can be written as a sum of positive squares in only one way, i.e., 209033764 + 9180900 = 14458^2 + 3030^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13638409 + ... + 13638424.

Almost surely, 2^218214664 is an apocalyptic number.

It is an amenable number.

218214664 is a deficient number, since it is larger than the sum of its proper divisors (190937846).

218214664 is a wasteful number, since it uses less digits than its factorization.

218214664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27276839 (or 27276835 counting only the distinct ones).

The product of its digits is 18432, while the sum is 34.

The square root of 218214664 is about 14772.0907118796. The cubic root of 218214664 is about 602.0436460962.

The spelling of 218214664 in words is "two hundred eighteen million, two hundred fourteen thousand, six hundred sixty-four".