216870664 has 8 divisors (see below), whose sum is σ = 406632510. Its totient is φ = 108435328.

The previous prime is 216870623. The next prime is 216870691. The reversal of 216870664 is 466078612.

216870664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 180364900 + 36505764 = 13430^2 + 6042^2 .

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, 13554409 + ... + 13554424.

Almost surely, 2^216870664 is an apocalyptic number.

It is an amenable number.

216870664 is a deficient number, since it is larger than the sum of its proper divisors (189761846).

216870664 is a wasteful number, since it uses less digits than its factorization.

216870664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27108839 (or 27108835 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 216870664 is about 14726.5292584505. The cubic root of 216870664 is about 600.8050896051.

The spelling of 216870664 in words is "two hundred sixteen million, eight hundred seventy thousand, six hundred sixty-four".