who invented the number zero??

The Babylonians invented it in 2000-1000BC but there are some tablets indicating somewhere between 800-400BC. The Greeks also came up with it at near the same time, but more so in a philosophical connotation. Pingala of India came up with it around 500-100BC but it was binary. The Mayans also had the idea of Zero or at least the concept of "nothing" during their classical period.

The Mayans

Early use of something like zero by the Indian scholar Pingala (circa 5th-2nd century BC), implied at first glance by his use of binary numbers, is only the modern binary representation using 0 and 1 applied to Pingala's binary system, which used short and long syllables (the latter equal in length to two short syllables), making it similar to Morse code. Nevertheless, he and other Indian scholars at the time used the Sanskrit word sunya (the origin of the word zero after a series of transliterations and a literal translation) to refer to zero or void.

it was invented by Indians

Ancient Indian mathematician,Aryabhatta has discovered concept of zero.