216297216 has 252 divisors, whose sum is σ = 692568520. Its totient is φ = 67184640.

The previous prime is 216297203. The next prime is 216297217. The reversal of 216297216 is 612792612.

216297216 is a `hidden beast` number, since 2 + 1 + 629 + 7 + 21 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216297217) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 3545826 + ... + 3545886.

Almost surely, 2^216297216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216297216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (346284260).

216297216 is an abundant number, since it is smaller than the sum of its proper divisors (476271304).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216297216 is an frugal number, since it uses more digits than its factorization.

216297216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 85 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 216297216 is about 14707.0464743945. The cubic root of 216297216 is about 600.2750738713.

The spelling of 216297216 in words is "two hundred sixteen million, two hundred ninety-seven thousand, two hundred sixteen".