199944519689 has 2 divisors, whose sum is σ = 199944519690. Its totient is φ = 199944519688.

The previous prime is 199944519637. The next prime is 199944519703. The reversal of 199944519689 is 986915449991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114154109689 + 85790410000 = 337867^2 + 292900^2 .

It is a cyclic number.

It is not a de Polignac number, because 199944519689 - 2⁸ = 199944519433 is a prime.

It is not a weakly prime, because it can be changed into another prime (199944519589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99972259844 + 99972259845.

It is an arithmetic number, because the mean of its divisors is an integer number (99972259845).

Almost surely, 2^199944519689 is an apocalyptic number.

It is an amenable number.

199944519689 is a deficient number, since it is larger than the sum of its proper divisors (1).

199944519689 is an equidigital number, since it uses as much as digits as its factorization.

199944519689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 226748160, while the sum is 74.

The spelling of 199944519689 in words is "one hundred ninety-nine billion, nine hundred forty-four million, five hundred nineteen thousand, six hundred eighty-nine".