216658668 has 12 divisors (see below), whose sum is σ = 505536920. Its totient is φ = 72219552.

The previous prime is 216658661. The next prime is 216658669. The reversal of 216658668 is 866856612.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a hoax number, since the sum of its digits (48) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (216658661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9027433 + ... + 9027456.

Almost surely, 2^216658668 is an apocalyptic number.

It is an amenable number.

216658668 is an abundant number, since it is smaller than the sum of its proper divisors (288878252).

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

216658668 is a wasteful number, since it uses less digits than its factorization.

216658668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18054896 (or 18054894 counting only the distinct ones).

The product of its digits is 829440, while the sum is 48.

The square root of 216658668 is about 14719.3297401750. The cubic root of 216658668 is about 600.6092589077.

The spelling of 216658668 in words is "two hundred sixteen million, six hundred fifty-eight thousand, six hundred sixty-eight".