code: def 					__lowerCAmelCase			(  _A					):
  
  
  
  							"""simple docstring"""
  
  
  							if not isinstance(_A ,_A					):
  														_lowercase				=	f'''Input value of [number={number}] must be an integer'''
  														raise TypeError(_A					)
  							if number < 0 or number % 2 == 1:
  														return False
  							_lowercase				=	int(number**0.5					)
  							return number == number_sqrt * (number_sqrt + 1)
  
  
  if __name__ == "__main__":
  				import doctest
  
  				doctest.testmod()
  
  
  
style_context: def 					__lowerCAmelCase			(  _A = 998_001					):
  
  
  
  							"""simple docstring"""
  
  
  							_lowercase				=	0
  							for i in range(999 ,99 ,-1					):  # 3 digit numbers range from 999 down to 100
  														for j in range(999 ,99 ,-1					):
  																					_lowercase				=	str(i * j					)
  																					if product_string == product_string[::-1] and i * j < n:
  																												_lowercase				=	max(_A ,i * j					)
  							return answer
  
  
  if __name__ == "__main__":
  				print(F'''{solution() = }''')
  
  
  