216384 has 84 divisors (see below), whose sum is σ = 694944. Its totient is φ = 59136.

The previous prime is 216379. The next prime is 216397. The reversal of 216384 is 483612.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (84).

It is a super-3 number, since 3×216384³ = 30394617960333312, which contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is one of the 548 Lynch-Bell numbers.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 216384.

It is an unprimeable number.

216384 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9397 + ... + 9419.

2²¹⁶³⁸⁴ is an apocalyptic number.

216384 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (347472).

216384 is an abundant number, since it is smaller than the sum of its proper divisors (478560).

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

216384 is a wasteful number, since it uses less digits than its factorization.

216384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52 (or 35 counting only the distinct ones).

The product of its digits is 1152, while the sum is 24.

The square root of 216384 is about 465.1709363234. The cubic root of 216384 is about 60.0355345064.

Adding to 216384 its reverse (483612), we get a palindrome (699996).

It can be divided in two parts, 216 and 384, that multiplied together give a square (82944 = 288²).

The spelling of 216384 in words is "two hundred sixteen thousand, three hundred eighty-four".