188909568 has 144 divisors (see below), whose sum is σ = 562374540. Its totient is φ = 61046784.

The previous prime is 188909561. The next prime is 188909569. The reversal of 188909568 is 865909881.

It can be written as a sum of positive squares in 2 ways, for example, as 188457984 + 451584 = 13728^2 + 672^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (188909561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 681846 + ... + 682122.

Almost surely, 2^188909568 is an apocalyptic number.

188909568 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 188909568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (281187270).

188909568 is an abundant number, since it is smaller than the sum of its proper divisors (373464972).

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

188909568 is a wasteful number, since it uses less digits than its factorization.

188909568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342 (or 319 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 54.

The square root of 188909568 is about 13744.4377113071. The cubic root of 188909568 is about 573.7878110272.

The spelling of 188909568 in words is "one hundred eighty-eight million, nine hundred nine thousand, five hundred sixty-eight".