Septbiunium (Sbu)
Septbiunium is the systematic name of the theoretical 721. element in the periodic table with a symbol of Sbu and atomic number of 721. Septbiunium, also known as element 721, has sebaʼ mija u wieħed u għoxrin protons in its nucleus, and sebaʼ mija u wieħed u għoxrin electrons in its shells.