The number 21 !=51,090,942,171,709,440,000 has over 60,000 positive integer divisors. One of them is chosen at random. What is the probability that it is odd?
Answer Choices
A. \dfrac{1}{21}
B. \dfrac{1}{19}
C. \dfrac{1}{18}
D. \dfrac{1}{2}
E. \dfrac{11}{21}