216421200 has 240 divisors, whose sum is σ = 798014400. Its totient is φ = 55641600.

The previous prime is 216421187. The next prime is 216421217. The reversal of 216421200 is 2124612.

216421200 is a `hidden beast` number, since 2 + 1 + 642 + 1 + 20 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 312855 + ... + 313545.

It is an arithmetic number, because the mean of its divisors is an integer number (3325060).

Almost surely, 2^216421200 is an apocalyptic number.

216421200 is a gapful number since it is divisible by the number (20) 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 216421200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (399007200).

216421200 is an abundant number, since it is smaller than the sum of its proper divisors (581593200).

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

216421200 is a wasteful number, since it uses less digits than its factorization.

216421200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 747 (or 730 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 216421200 is about 14711.2609928585. The cubic root of 216421200 is about 600.3897467743.

Adding to 216421200 its reverse (2124612), we get a palindrome (218545812).

The spelling of 216421200 in words is "two hundred sixteen million, four hundred twenty-one thousand, two hundred".