189998172 has 144 divisors (see below), whose sum is σ = 601735680. Its totient is φ = 49209984.

The previous prime is 189998129. The next prime is 189998173. The reversal of 189998172 is 271899981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189998173) 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 47 ways as a sum of consecutive naturals, for example, 192793 + ... + 193775.

It is an arithmetic number, because the mean of its divisors is an integer number (4178720).

Almost surely, 2^189998172 is an apocalyptic number.

189998172 is a gapful number since it is divisible by the number (12) 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 189998172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (300867840).

189998172 is an abundant number, since it is smaller than the sum of its proper divisors (411737508).

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

189998172 is a wasteful number, since it uses less digits than its factorization.

189998172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1072 (or 1067 counting only the distinct ones).

The product of its digits is 653184, while the sum is 54.

The square root of 189998172 is about 13783.9824434015. The cubic root of 189998172 is about 574.8878642072.

The spelling of 189998172 in words is "one hundred eighty-nine million, nine hundred ninety-eight thousand, one hundred seventy-two".