216644664 has 32 divisors (see below), whose sum is σ = 554209920. Its totient is φ = 70535136.

The previous prime is 216644633. The next prime is 216644711. The reversal of 216644664 is 466446612.

216644664 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 103932 + ... + 105995.

It is an arithmetic number, because the mean of its divisors is an integer number (17319060).

Almost surely, 2^216644664 is an apocalyptic number.

216644664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

216644664 is an abundant number, since it is smaller than the sum of its proper divisors (337565256).

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

216644664 is a wasteful number, since it uses less digits than its factorization.

216644664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209979 (or 209975 counting only the distinct ones).

The product of its digits is 165888, while the sum is 39.

The square root of 216644664 is about 14718.8540314795. The cubic root of 216644664 is about 600.5963182557.

The spelling of 216644664 in words is "two hundred sixteen million, six hundred forty-four thousand, six hundred sixty-four".