216218864 has 20 divisors (see below), whose sum is σ = 419932200. Its totient is φ = 107849280.

The previous prime is 216218851. The next prime is 216218887. The reversal of 216218864 is 468812612.

It is a happy number.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a zygodrome in base 2.

It is a congruent number.

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, 9314 + ... + 22785.

It is an arithmetic number, because the mean of its divisors is an integer number (20996610).

Almost surely, 2^216218864 is an apocalyptic number.

It is an amenable number.

216218864 is a deficient number, since it is larger than the sum of its proper divisors (203713336).

216218864 is a wasteful number, since it uses less digits than its factorization.

216218864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32528 (or 32522 counting only the distinct ones).

The product of its digits is 36864, while the sum is 38.

The square root of 216218864 is about 14704.3824759831. The cubic root of 216218864 is about 600.2025834441.

The spelling of 216218864 in words is "two hundred sixteen million, two hundred eighteen thousand, eight hundred sixty-four".