216321420 has 96 divisors (see below), whose sum is σ = 695794176. Its totient is φ = 49190400.

The previous prime is 216321389. The next prime is 216321431. The reversal of 216321420 is 24123612.

216321420 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 87400 + ... + 89840.

It is an arithmetic number, because the mean of its divisors is an integer number (7247856).

Almost surely, 2^216321420 is an apocalyptic number.

216321420 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 216321420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (347897088).

216321420 is an abundant number, since it is smaller than the sum of its proper divisors (479472756).

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

216321420 is a wasteful number, since it uses less digits than its factorization.

216321420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2671 (or 2669 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 216321420 is about 14707.8693222370. The cubic root of 216321420 is about 600.2974636124.

The spelling of 216321420 in words is "two hundred sixteen million, three hundred twenty-one thousand, four hundred twenty".