199579561 has 2 divisors, whose sum is σ = 199579562. Its totient is φ = 199579560.

The previous prime is 199579543. The next prime is 199579577. The reversal of 199579561 is 165975991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 106090000 + 93489561 = 10300^2 + 9669^2 .

It is an emirp because it is prime and its reverse (165975991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199579561 - 2⁷ = 199579433 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 199579499 and 199579508.

It is not a weakly prime, because it can be changed into another prime (199579361) 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, 99789780 + 99789781.

It is an arithmetic number, because the mean of its divisors is an integer number (99789781).

Almost surely, 2^199579561 is an apocalyptic number.

It is an amenable number.

199579561 is a deficient number, since it is larger than the sum of its proper divisors (1).

199579561 is an equidigital number, since it uses as much as digits as its factorization.

199579561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 765450, while the sum is 52.

The square root of 199579561 is about 14127.2630399522. The cubic root of 199579561 is about 584.3934697890.

The spelling of 199579561 in words is "one hundred ninety-nine million, five hundred seventy-nine thousand, five hundred sixty-one".