Pentbiunium (Pbu)

Pentbiunium is the systematic name of the theoretical ที่ 521 element in the periodic table with a symbol of Pbu and atomic number of 521. Pentbiunium, also known as element 521, has ห้า​ร้อย​ยี่​สิบ​เอ็ด protons in its nucleus, and ห้า​ร้อย​ยี่​สิบ​เอ็ด electrons in its shells.