161884728 has 192 divisors, whose sum is σ = 487468800. Its totient is φ = 48384000.

The previous prime is 161884721. The next prime is 161884747. The reversal of 161884728 is 827488161.

161884728 is a `hidden beast` number, since 1 + 618 + 8 + 4 + 7 + 28 = 666.

161884728 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161884721) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2653818 + ... + 2653878.

It is an arithmetic number, because the mean of its divisors is an integer number (2538900).

Almost surely, 2^161884728 is an apocalyptic number.

161884728 is a gapful number since it is divisible by the number (18) 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 161884728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243734400).

161884728 is an abundant number, since it is smaller than the sum of its proper divisors (325584072).

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

161884728 is a wasteful number, since it uses less digits than its factorization.

161884728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174 (or 167 counting only the distinct ones).

The product of its digits is 172032, while the sum is 45.

The square root of 161884728 is about 12723.3929437081. The cubic root of 161884728 is about 545.0068489446.

The spelling of 161884728 in words is "one hundred sixty-one million, eight hundred eighty-four thousand, seven hundred twenty-eight".