199975609 has 2 divisors, whose sum is σ = 199975610. Its totient is φ = 199975608.

The previous prime is 199975591. The next prime is 199975621. The reversal of 199975609 is 906579991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111239209 + 88736400 = 10547^2 + 9420^2 .

It is a cyclic number.

It is not a de Polignac number, because 199975609 - 2⁷ = 199975481 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 199975609.

It is not a weakly prime, because it can be changed into another prime (199975669) 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, 99987804 + 99987805.

It is an arithmetic number, because the mean of its divisors is an integer number (99987805).

Almost surely, 2^199975609 is an apocalyptic number.

It is an amenable number.

199975609 is a deficient number, since it is larger than the sum of its proper divisors (1).

199975609 is an equidigital number, since it uses as much as digits as its factorization.

199975609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1377810, while the sum is 55.

The square root of 199975609 is about 14141.2732453623. The cubic root of 199975609 is about 584.7797734372.

The spelling of 199975609 in words is "one hundred ninety-nine million, nine hundred seventy-five thousand, six hundred nine".