216978663 has 8 divisors (see below), whose sum is σ = 315605376. Its totient is φ = 131502200.

The previous prime is 216978653. The next prime is 216978679. The reversal of 216978663 is 366879612.

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

It is a cyclic number.

It is not a de Polignac number, because 216978663 - 2⁸ = 216978407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216978623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3287523 + ... + 3287588.

It is an arithmetic number, because the mean of its divisors is an integer number (39450672).

Almost surely, 2^216978663 is an apocalyptic number.

216978663 is a deficient number, since it is larger than the sum of its proper divisors (98626713).

216978663 is a wasteful number, since it uses less digits than its factorization.

216978663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6575125.

The product of its digits is 653184, while the sum is 48.

The square root of 216978663 is about 14730.1956198823. The cubic root of 216978663 is about 600.9048043072.

It can be divided in two parts, 216 and 978663, that added together give a palindrome (978879).

The spelling of 216978663 in words is "two hundred sixteen million, nine hundred seventy-eight thousand, six hundred sixty-three".