Are UTRs part of exons?

Exons:

1. The nucleotide sequence in mRNA.
2. It codes for proteins i.e. DNA bases that are translated to proteins.
3. Found in both prokaryotes and eukaryotes

UTRs:

1. These are the untranslated regions in the 5' region of the start codon on mRNA & 3' region of the stop codon.
2. They are a part of exons.