216115665 has 8 divisors (see below), whose sum is σ = 345785088. Its totient is φ = 115261680.

The previous prime is 216115651. The next prime is 216115703. The reversal of 216115665 is 566511612.

216115665 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 not a de Polignac number, because 216115665 - 2¹² = 216111569 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax 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, 7203841 + ... + 7203870.

It is an arithmetic number, because the mean of its divisors is an integer number (43223136).

Almost surely, 2^216115665 is an apocalyptic number.

It is an amenable number.

216115665 is a deficient number, since it is larger than the sum of its proper divisors (129669423).

216115665 is a wasteful number, since it uses less digits than its factorization.

216115665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14407719.

The product of its digits is 10800, while the sum is 33.

The square root of 216115665 is about 14700.8729332649. The cubic root of 216115665 is about 600.1070781115.

The spelling of 216115665 in words is "two hundred sixteen million, one hundred fifteen thousand, six hundred sixty-five".