188899986 has 32 divisors (see below), whose sum is σ = 412796736. Its totient is φ = 57152000.

The previous prime is 188899969. The next prime is 188899987. The reversal of 188899986 is 689998881.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is not an unprimeable number, because it can be changed into a prime (188899987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48346 + ... + 52106.

It is an arithmetic number, because the mean of its divisors is an integer number (12899898).

Almost surely, 2^188899986 is an apocalyptic number.

188899986 is an abundant number, since it is smaller than the sum of its proper divisors (223896750).

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

188899986 is a wasteful number, since it uses less digits than its factorization.

188899986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4538.

The product of its digits is 17915904, while the sum is 66.

The square root of 188899986 is about 13744.0891295131. The cubic root of 188899986 is about 573.7781095108.

The spelling of 188899986 in words is "one hundred eighty-eight million, eight hundred ninety-nine thousand, nine hundred eighty-six".