216021384 has 32 divisors (see below), whose sum is σ = 600060000. Its totient is φ = 72007056.

The previous prime is 216021383. The next prime is 216021389. The reversal of 216021384 is 483120612.

216021384 is a `hidden beast` number, since 21 + 602 + 1 + 38 + 4 = 666.

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

216021384 is a modest number, since divided by 21384 gives 216 as remainder.

It is not an unprimeable number, because it can be changed into a prime (216021383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 499834 + ... + 500265.

It is an arithmetic number, because the mean of its divisors is an integer number (18751875).

Almost surely, 2^216021384 is an apocalyptic number.

216021384 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

216021384 is an abundant number, since it is smaller than the sum of its proper divisors (384038616).

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

216021384 is a wasteful number, since it uses less digits than its factorization.

216021384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000114 (or 1000104 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 216021384 is about 14697.6659371480. The cubic root of 216021384 is about 600.0197993466.

Adding to 216021384 its reverse (483120612), we get a palindrome (699141996).

The spelling of 216021384 in words is "two hundred sixteen million, twenty-one thousand, three hundred eighty-four".