Answer :

Pulkit
From the ques, it can be said that the answer would be less than 1000000
Start from 999,
999*999= 998001
Therefore, 998001 is a greatest number of square 999.
AL2006
A "perfect square" is an integer that is the square of an integer.

The largest 6-digit integer is 999,999.

The square root of it is 999.9995

So the greatest square of an integer is the square of 999 = 998,001 .