This cannot be answered because the common multiples of any two or more numbers are infinite.
There is no highest common multiple of 56, 98 and 168. Their highest common factor, which you may have meant, is 14.
The least common multiple of 3, 21, and 56 is 168.
The Least Common Multiple (LCM) for 28 21 56 is 168.
The least common multiple (LCM) of 21, 56, and 63 is 504.
The greatest, (Highest) Common Factor of 21 and 56 is 7
The greatest common multiple of any set of integers is infinite.
The GCF of 35 and 56 is 7.The LCM of 35 and 56 is 280.
840
The GCF is 7.
The highest common factor is 7
The least common multiple (LCM) of 18, 21, and 56 is 504.
The least common multiple of 21 and 56 is 168.The least common multiple (LCM) is often also called the lowest common multiple or smallest common multiple. Keep in mind that these different terms all refer to the same thing: the smallest positive integer which is a multiple of two or more numbers.