188011920 has 80 divisors (see below), whose sum is σ = 588265920. Its totient is φ = 49669632.

The previous prime is 188011919. The next prime is 188011921. The reversal of 188011920 is 29110881.

It is an interprime number because it is at equal distance from previous prime (188011919) and next prime (188011921).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (188011921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22567 + ... + 29753.

It is an arithmetic number, because the mean of its divisors is an integer number (7353324).

Almost surely, 2^188011920 is an apocalyptic number.

188011920 is a gapful number since it is divisible by the number (10) 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 188011920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294132960).

188011920 is an abundant number, since it is smaller than the sum of its proper divisors (400254000).

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

188011920 is a wasteful number, since it uses less digits than its factorization.

188011920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7312 (or 7306 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 30.

The square root of 188011920 is about 13711.7438715869. The cubic root of 188011920 is about 572.8775387111.

The spelling of 188011920 in words is "one hundred eighty-eight million, eleven thousand, nine hundred twenty".