216371666 has 8 divisors (see below), whose sum is σ = 370922880. Its totient is φ = 92730708.

The previous prime is 216371653. The next prime is 216371689. The reversal of 216371666 is 666173612.

It is a happy number.

216371666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

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, 7727546 + ... + 7727573.

It is an arithmetic number, because the mean of its divisors is an integer number (46365360).

Almost surely, 2^216371666 is an apocalyptic number.

216371666 is a deficient number, since it is larger than the sum of its proper divisors (154551214).

216371666 is a wasteful number, since it uses less digits than its factorization.

216371666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15455128.

The product of its digits is 54432, while the sum is 38.

The square root of 216371666 is about 14709.5773562669. The cubic root of 216371666 is about 600.3439379919.

The spelling of 216371666 in words is "two hundred sixteen million, three hundred seventy-one thousand, six hundred sixty-six".