The IUPAC name of amine is N,N-diethylbutan-1-amine.
In secondary and tertiary amines, the largest alkyl group is considered as parent alkane and other alkyl groups as N-substituents.
The parent compound contains 4 C atoms and a amino group. Hence, it is named butanamine. The last alphabet e from butane is replaced with word amine. The position of the amino group is indicated by lowest locant. Two ethyl groups are present as substituents on N atom and are written as N,N-diethyl. N indicates that the substituent is on N atom.