What is the meaning of Quadrillion?

A thousand trillion (logic: 1,000 × 1,000): 1 followed by fifteen zeros, 10.

A million trillion (logic: 1,000,000): 1 followed by twenty-four zeros, 10.

Any very large number, exceeding normal description.

septillion (10)

quadrillion (10)

quadrillion (10)

Source: wiktionary.org