216021456 has 120 divisors (see below), whose sum is σ = 707913024. Its totient is φ = 60203520.

The previous prime is 216021437. The next prime is 216021457. The reversal of 216021456 is 654120612.

216021456 is a `hidden beast` number, since 2 + 1 + 602 + 1 + 4 + 56 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216021457) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38715 + ... + 43941.

Almost surely, 2^216021456 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 216021456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (353956512).

216021456 is an abundant number, since it is smaller than the sum of its proper divisors (491891568).

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

216021456 is a wasteful number, since it uses less digits than its factorization.

216021456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5289 (or 5280 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 216021456 is about 14697.6683865163. The cubic root of 216021456 is about 600.0198660089.

The spelling of 216021456 in words is "two hundred sixteen million, twenty-one thousand, four hundred fifty-six".