216188730 has 128 divisors (see below), whose sum is σ = 621527040. Its totient is φ = 53317440.

The previous prime is 216188729. The next prime is 216188737. The reversal of 216188730 is 37881612.

216188730 is a `hidden beast` number, since 2 + 1 + 618 + 8 + 7 + 30 = 666.

It is not an unprimeable number, because it can be changed into a prime (216188737) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 191949 + ... + 193071.

It is an arithmetic number, because the mean of its divisors is an integer number (4855680).

Almost surely, 2^216188730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216188730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310763520).

216188730 is an abundant number, since it is smaller than the sum of its proper divisors (405338310).

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

216188730 is a wasteful number, since it uses less digits than its factorization.

216188730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1193 (or 1187 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 216188730 is about 14703.3577797726. The cubic root of 216188730 is about 600.1746991288.

The spelling of 216188730 in words is "two hundred sixteen million, one hundred eighty-eight thousand, seven hundred thirty".