Need Help With Coded Message

[Sergio Rodriguez]

So,

An Ex-friend of mine has been spamming me with messages but they are coded messages and i dont know what code they are. If anybody knows what code it is please can they tell me as he has been spamming it to all my friends. The code is here

57687920736f206465707265737365643f2049742773204368726973746d61732065766521

 

[rat]

Why so depressed? It's Christmas eve!

It was hexadecimal, the f's kind of gave it away.

 

[Sergio Rodriguez]

THANK YOU SO MUCH, LOVE YOU.
[DOUBLEPOST=1482621788,1482621577][/DOUBLEPOST]He sent me another code which isnt hexadecimal
3.96115418006E+40
[DOUBLEPOST=1482622288][/DOUBLEPOST]I cant find out the last code he sent

3.96115418006E+40

 

[rat]

Idk what it means but it's the mathematical dention for a number:

39611541800600000000000000000000000000000