199968539 has 2 divisors, whose sum is σ = 199968540.
Its totient is φ = 199968538.
The previous prime is 199968481. The next prime is 199968541. The reversal of 199968539 is 935869991.
It is a strong prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-199968539 is a prime.
Together with 199968541, it forms a pair of twin primes.
It is a Chen prime.
It is not a weakly prime, because it can be changed into another prime (199968599) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (17) of ones.
It is a good prime.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99984269 + 99984270.
It is an arithmetic number, because the mean of its divisors is an integer number (99984270).
Almost surely, 2199968539 is an apocalyptic number.
199968539 is a deficient number, since it is larger than the sum of its proper divisors (1).
199968539 is an equidigital number, since it uses as much as digits as its factorization.
199968539 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 4723920, while the sum is 59.
The square root of 199968539 is about 14141.0232656622.
The cubic root of 199968539 is about 584.7728818605.
The spelling of 199968539 in words is "one hundred ninety-nine million, nine hundred sixty-eight thousand, five hundred thirty-nine".