199549273409 has 4 divisors (see below), whose sum is σ = 204416328900. Its totient is φ = 194682217920.

The previous prime is 199549273369. The next prime is 199549273421. The reversal of 199549273409 is 904372945991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 40774917184 + 158774356225 = 201928^2 + 398465^2 .

It is a cyclic number.

It is not a de Polignac number, because 199549273409 - 2¹² = 199549269313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199549273439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2433527684 + ... + 2433527765.

It is an arithmetic number, because the mean of its divisors is an integer number (51104082225).

Almost surely, 2^199549273409 is an apocalyptic number.

It is an amenable number.

199549273409 is a deficient number, since it is larger than the sum of its proper divisors (4867055491).

199549273409 is an equidigital number, since it uses as much as digits as its factorization.

199549273409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4867055490.

The product of its (nonzero) digits is 22044960, while the sum is 62.

The spelling of 199549273409 in words is "one hundred ninety-nine billion, five hundred forty-nine million, two hundred seventy-three thousand, four hundred nine".