199707477021 has 32 divisors (see below), whose sum is σ = 320913936000. Its totient is φ = 122012728704.

The previous prime is 199707477019. The next prime is 199707477037. The reversal of 199707477021 is 120774707991.

It is not a de Polignac number, because 199707477021 - 2¹ = 199707477019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199707477061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1997856 + ... + 2095433.

It is an arithmetic number, because the mean of its divisors is an integer number (10028560500).

Almost surely, 2^199707477021 is an apocalyptic number.

It is an amenable number.

199707477021 is a deficient number, since it is larger than the sum of its proper divisors (121206458979).

199707477021 is a wasteful number, since it uses less digits than its factorization.

199707477021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4093450 (or 4093444 counting only the distinct ones).

The product of its (nonzero) digits is 1555848, while the sum is 54.

The spelling of 199707477021 in words is "one hundred ninety-nine billion, seven hundred seven million, four hundred seventy-seven thousand, twenty-one".