test = "word 123 456 123 7890.000 0.12000"

 StringSplit[test , Whitespace] // Select[IntegerQ@*ToExpression]

 SemanticImportString[test] // Normal // First // Select[IntegerQ]
 
 With [{t = TextWords[test]}, 
 t // StringContainsQ[Except[DigitCharacter]] // Pick[t, #, False] &]


> {"123", "456", "123"}