199991573 has 2 divisors, whose sum is σ = 199991574. Its totient is φ = 199991572.

The previous prime is 199991567. The next prime is 199991669. The reversal of 199991573 is 375199991.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 174821284 + 25170289 = 13222^2 + 5017^2 .

It is an emirp because it is prime and its reverse (375199991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199991573 - 2⁴ = 199991557 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199991273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99995786 + 99995787.

It is an arithmetic number, because the mean of its divisors is an integer number (99995787).

Almost surely, 2^199991573 is an apocalyptic number.

It is an amenable number.

199991573 is a deficient number, since it is larger than the sum of its proper divisors (1).

199991573 is an equidigital number, since it uses as much as digits as its factorization.

199991573 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 688905, while the sum is 53.

The square root of 199991573 is about 14141.8376811502. The cubic root of 199991573 is about 584.7953339614.

The spelling of 199991573 in words is "one hundred ninety-nine million, nine hundred ninety-one thousand, five hundred seventy-three".