199999988 has 12 divisors (see below), whose sum is σ = 350304612. Its totient is φ = 99912960.

The previous prime is 199999963. The next prime is 199999991. The reversal of 199999988 is 889999991.

It can be written as a sum of positive squares in 2 ways, for example, as 174979984 + 25020004 = 13228^2 + 5002^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16445 + ... + 25892.

It is an arithmetic number, because the mean of its divisors is an integer number (29192051).

Almost surely, 2^199999988 is an apocalyptic number.

It is an amenable number.

199999988 is a deficient number, since it is larger than the sum of its proper divisors (150304624).

199999988 is a wasteful number, since it uses less digits than its factorization.

199999988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43522 (or 43520 counting only the distinct ones).

The product of its digits is 34012224, while the sum is 71.

The square root of 199999988 is about 14142.1351994669. The cubic root of 199999988 is about 584.8035359465.

The spelling of 199999988 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighty-eight".