Is point to point distance calculations heavy in oracle ?

I am designing an application to do GEO/RF mapping and need to crunch some numbers specifically the distance between points. I will be using great circle distance calculations with given latitude and longitude points :

var R = 6371; // km
var dLat = (lat2-lat1).toRad();
var dLon = (lon2-lon1).toRad();
var a = Math.sin(dLat/2) * Math.sin(dLat/2) +
        Math.cos(lat1.toRad()) * Math.cos(lat2.toRad()) *
        Math.sin(dLon/2) * Math.sin(dLon/2);
var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
var d = R * c;

If I had to calculate distances between 500,000 points,  would this take a long time and is it worth pursuing via pl/sql or should this be done in java or python ... something like that ?