216889928 has 16 divisors (see below), whose sum is σ = 407306880. Its totient is φ = 108274768.

The previous prime is 216889909. The next prime is 216889943. The reversal of 216889928 is 829988612.

It is a self number, because there is not a number n which added to its sum of digits gives 216889928.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15776 + ... + 26127.

It is an arithmetic number, because the mean of its divisors is an integer number (25456680).

Almost surely, 2^216889928 is an apocalyptic number.

It is an amenable number.

216889928 is a deficient number, since it is larger than the sum of its proper divisors (190416952).

216889928 is a wasteful number, since it uses less digits than its factorization.

216889928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42556 (or 42552 counting only the distinct ones).

The product of its digits is 995328, while the sum is 53.

The square root of 216889928 is about 14727.1833016365. The cubic root of 216889928 is about 600.8228783435.

The spelling of 216889928 in words is "two hundred sixteen million, eight hundred eighty-nine thousand, nine hundred twenty-eight".