198990000 has 400 divisors, whose sum is σ = 790247040. Its totient is φ = 47520000.

The previous prime is 198989977. The next prime is 198990007. The reversal of 198990000 is 99891.

198990000 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (400).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (198990007) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2969967 + ... + 2970033.

Almost surely, 2^198990000 is an apocalyptic number.

198990000 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 198990000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395123520).

198990000 is an abundant number, since it is smaller than the sum of its proper divisors (591257040).

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

198990000 is a wasteful number, since it uses less digits than its factorization.

198990000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 36.

The square root of 198990000 is about 14106.3815346105. The cubic root of 198990000 is about 583.8174665667.

The spelling of 198990000 in words is "one hundred ninety-eight million, nine hundred ninety thousand".