216828 has 36 divisors (see below), whose sum is σ = 578760. Its totient is φ = 68256.

The previous prime is 216803. The next prime is 216829. The reversal of 216828 is 828612.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216829) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 526 + ... + 842.

2²¹⁶⁸²⁸ 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 216828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289380).

216828 is an abundant number, since it is smaller than the sum of its proper divisors (361932).

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

216828 is a wasteful number, since it uses less digits than its factorization.

216828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346 (or 341 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 216828 is about 465.6479356767. The cubic root of 216828 is about 60.0765689118.

The spelling of 216828 in words is "two hundred sixteen thousand, eight hundred twenty-eight".