216309204 has 60 divisors (see below), whose sum is σ = 590081184. Its totient is φ = 68965776.

The previous prime is 216309157. The next prime is 216309209. The reversal of 216309204 is 402903612.

216309204 is a `hidden beast` number, since 2 + 1 + 630 + 9 + 20 + 4 = 666.

It is a super-2 number, since 2×216309204² = 93579343470227232, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216309209) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7062 + ... + 21965.

Almost surely, 2^216309204 is an apocalyptic number.

It is an amenable number.

216309204 is an abundant number, since it is smaller than the sum of its proper divisors (373771980).

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

216309204 is a wasteful number, since it uses less digits than its factorization.

216309204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29066 (or 29055 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 216309204 is about 14707.4540284850. The cubic root of 216309204 is about 600.2861634957.

The spelling of 216309204 in words is "two hundred sixteen million, three hundred nine thousand, two hundred four".