199731728 has 20 divisors (see below), whose sum is σ = 442263360. Its totient is φ = 85599264.

The previous prime is 199731713. The next prime is 199731737. The reversal of 199731728 is 827137991.

199731728 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 891548 + ... + 891771.

It is an arithmetic number, because the mean of its divisors is an integer number (22113168).

Almost surely, 2^199731728 is an apocalyptic number.

It is an amenable number.

199731728 is an abundant number, since it is smaller than the sum of its proper divisors (242531632).

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

199731728 is a wasteful number, since it uses less digits than its factorization.

199731728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1783334 (or 1783328 counting only the distinct ones).

The product of its digits is 190512, while the sum is 47.

The square root of 199731728 is about 14132.6475934271. The cubic root of 199731728 is about 584.5419532814.

The spelling of 199731728 in words is "one hundred ninety-nine million, seven hundred thirty-one thousand, seven hundred twenty-eight".