199763561 has 2 divisors, whose sum is σ = 199763562. Its totient is φ = 199763560.

The previous prime is 199763539. The next prime is 199763567. The reversal of 199763561 is 165367991.

It is a happy number.

199763561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199685161 + 78400 = 14131^2 + 280^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199763561 is a prime.

It is not a weakly prime, because it can be changed into another prime (199763567) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99881780 + 99881781.

It is an arithmetic number, because the mean of its divisors is an integer number (99881781).

Almost surely, 2^199763561 is an apocalyptic number.

It is an amenable number.

199763561 is a deficient number, since it is larger than the sum of its proper divisors (1).

199763561 is an equidigital number, since it uses as much as digits as its factorization.

199763561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 306180, while the sum is 47.

The square root of 199763561 is about 14133.7737706530. The cubic root of 199763561 is about 584.5730061604.

The spelling of 199763561 in words is "one hundred ninety-nine million, seven hundred sixty-three thousand, five hundred sixty-one".