199921659876 has 27 divisors (see below), whose sum is σ = 505364310633. Its totient is φ = 66639659040.

The previous prime is 199921659793. The next prime is 199921659907. The reversal of 199921659876 is 678956129991.

The square root of 199921659876 is 447126.

It is a perfect power (a square), and thus also a powerful number.

199921659876 is a `hidden beast` number, since 1 + 9 + 9 + 9 + 21 + 6 + 598 + 7 + 6 = 666.

199921659876 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 137141346276 + 62780313600 = 370326^2 + 250560^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2645496 + ... + 2720016.

Almost surely, 2^199921659876 is an apocalyptic number.

199921659876 is the 447126-th square number.

It is an amenable number.

199921659876 is an abundant number, since it is smaller than the sum of its proper divisors (305442650757).

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

199921659876 is an frugal number, since it uses more digits than its factorization.

199921659876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149052 (or 74526 counting only the distinct ones).

The product of its digits is 132269760, while the sum is 72.

The spelling of 199921659876 in words is "one hundred ninety-nine billion, nine hundred twenty-one million, six hundred fifty-nine thousand, eight hundred seventy-six".