With this information, you can calculate the quantity of knots 646 miles per hour is equal to.

¿What is the inverse calculation between 1 knot and 646 miles per hour?

Performing the inverse calculation of the relationship between units, we obtain that 1 knot is 0.0017813923 times 646 miles per hour.

Which is the same to say that 646 miles per hour is 561.35865 knots.

Six hundred forty-six miles per hour equals to five hundred sixty-one knots. *Approximation

A knot is zero times six hundred forty-six miles per hour. *Approximation