189999368820 has 480 divisors, whose sum is σ = 666925902720. Its totient is φ = 44998778880.

The previous prime is 189999368813. The next prime is 189999368873. The reversal of 189999368820 is 28863999981.

It is a happy number.

189999368820 is a `hidden beast` number, since 18 + 99 + 99 + 368 + 82 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 173198512 + ... + 173199608.

It is an arithmetic number, because the mean of its divisors is an integer number (1389428964).

Almost surely, 2^189999368820 is an apocalyptic number.

189999368820 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 189999368820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (333462951360).

189999368820 is an abundant number, since it is smaller than the sum of its proper divisors (476926533900).

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

189999368820 is a wasteful number, since it uses less digits than its factorization.

189999368820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1485 (or 1474 counting only the distinct ones).

The product of its (nonzero) digits is 120932352, while the sum is 72.

The spelling of 189999368820 in words is "one hundred eighty-nine billion, nine hundred ninety-nine million, three hundred sixty-eight thousand, eight hundred twenty".