Is da‘wah to Allah considered an act of worship, and why is it separated from worship when the Ummah is described as a "Ummah of worship and da‘wah"?

Calling to Allah is a great act of worship, for which Allah chose the prophets and made their followers their inheritors, as substantiated by His saying, the Most High: "And who is better in speech than one who invites to Allah and does righteousness and says, 'Indeed, I am of the Muslims,'" and the saying of the Prophet, peace and blessings be upon him: "The scholars are the inheritors of the prophets." The phrase "our religion is a religion of worship and da'wah [calling to Allah]" might mean combining the specific with the general to show the virtue and importance of da'wah, or to clarify that Islam is more comprehensive than mere outward rituals, encompassing da'wah and other branches of faith.