216644328 has 128 divisors (see below), whose sum is σ = 653184000. Its totient is φ = 66263040.

The previous prime is 216644317. The next prime is 216644339. The reversal of 216644328 is 823446612.

216644328 is a `hidden beast` number, since 2 + 1 + 6 + 644 + 3 + 2 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (216644317) and next prime (216644339).

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a junction number, because it is equal to n+sod(n) for n = 216644292 and 216644301.

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, 149833 + ... + 151271.

It is an arithmetic number, because the mean of its divisors is an integer number (5103000).

Almost surely, 2^216644328 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 216644328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326592000).

216644328 is an abundant number, since it is smaller than the sum of its proper divisors (436539672).

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

216644328 is a wasteful number, since it uses less digits than its factorization.

216644328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1512 (or 1502 counting only the distinct ones).

The product of its digits is 55296, while the sum is 36.

The square root of 216644328 is about 14718.8426175430. The cubic root of 216644328 is about 600.5960077619.

The spelling of 216644328 in words is "two hundred sixteen million, six hundred forty-four thousand, three hundred twenty-eight".