199809563 has 2 divisors, whose sum is σ = 199809564. Its totient is φ = 199809562.

The previous prime is 199809521. The next prime is 199809569. The reversal of 199809563 is 365908991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 199809563 - 2⁶ = 199809499 is a prime.

It is a super-2 number, since 2×199809563² = 79847722932501938, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (199809569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99904781 + 99904782.

It is an arithmetic number, because the mean of its divisors is an integer number (99904782).

Almost surely, 2^199809563 is an apocalyptic number.

199809563 is a deficient number, since it is larger than the sum of its proper divisors (1).

199809563 is an equidigital number, since it uses as much as digits as its factorization.

199809563 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 524880, while the sum is 50.

The square root of 199809563 is about 14135.4010555060. The cubic root of 199809563 is about 584.6178749765.

The spelling of 199809563 in words is "one hundred ninety-nine million, eight hundred nine thousand, five hundred sixty-three".