199725687424 has 32 divisors (see below), whose sum is σ = 408644838900. Its totient is φ = 97163845632.

The previous prime is 199725687407. The next prime is 199725687481. The reversal of 199725687424 is 424786527991.

It can be written as a sum of positive squares in 2 ways, for example, as 195187240000 + 4538447424 = 441800^2 + 67368^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (64).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21081169 + ... + 21090640.

Almost surely, 2^199725687424 is an apocalyptic number.

It is an amenable number.

199725687424 is an abundant number, since it is smaller than the sum of its proper divisors (208919151476).

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

199725687424 is an equidigital number, since it uses as much as digits as its factorization.

199725687424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42171860 (or 42171848 counting only the distinct ones).

The product of its digits is 60963840, while the sum is 64.

The spelling of 199725687424 in words is "one hundred ninety-nine billion, seven hundred twenty-five million, six hundred eighty-seven thousand, four hundred twenty-four".