216555216 has 40 divisors (see below), whose sum is σ = 565213824. Its totient is φ = 71439360.

The previous prime is 216555203. The next prime is 216555223. The reversal of 216555216 is 612555612.

216555216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 18600 + ... + 27911.

Almost surely, 2^216555216 is an apocalyptic number.

It is an amenable number.

216555216 is an abundant number, since it is smaller than the sum of its proper divisors (348658608).

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

216555216 is a wasteful number, since it uses less digits than its factorization.

216555216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46619 (or 46613 counting only the distinct ones).

The product of its digits is 18000, while the sum is 33.

The square root of 216555216 is about 14715.8151660042. The cubic root of 216555216 is about 600.5136490379.

The spelling of 216555216 in words is "two hundred sixteen million, five hundred fifty-five thousand, two hundred sixteen".