2 * 57896044618658097711785492504343953926418782139537452191302581570759080747169 = 1 (mod n)

Multiplying a point by this number will "half" the point.

How do I multiply a point by the number?
private key 3

x =  f9308a019258c31049344f85f89d5229b531c845836f99b08601f113bce036f9
y =  388f7b0f632de8140fe337e62a37f3566500a99934c2231b6cb9fd7584b8e672

half of the above public key is 1 given below

x =  79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798
y =  483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8

How to half to multiply  f9308a019258c31049344f85f89d5229b531c845836f99b08601f113bce036f9 to get to 79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798?