199999900 has 72 divisors (see below), whose sum is σ = 466282656. Its totient is φ = 74188800.

The previous prime is 199999889. The next prime is 199999901. The reversal of 199999900 is 9999991.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199999901) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 119872 + ... + 121528.

It is an arithmetic number, because the mean of its divisors is an integer number (6476148).

Almost surely, 2^199999900 is an apocalyptic number.

199999900 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 199999900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (233141328).

199999900 is an abundant number, since it is smaller than the sum of its proper divisors (266282756).

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

199999900 is a wasteful number, since it uses less digits than its factorization.

199999900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1759 (or 1752 counting only the distinct ones).

The product of its (nonzero) digits is 531441, while the sum is 55.

The square root of 199999900 is about 14142.1320881966. The cubic root of 199999900 is about 584.8034501753.

The spelling of 199999900 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred".