Short answer: There is none.
There is not a least common multiple of a single number, such as 54, because there cannot be any form of common multiple without two or more numbers to compare. Common multiples are multiples that the numbers being compared have in common. The least common multiple is the smallest multiple that all the numbers being compared have in common. Thus, since there are not two or more numbers to compare, there is not a least common multiple.
The lowest common multiple of 54 depends upon the other number(s) with which it has COMMON multiples and is one of the multiples of 54. The common multiples of 54 depends upon the other numbers with which 54 has COMMON multiples and are the multiples of the least common multiples between 54 and the other number(s).
Least common multiple of 6 and 54 is 54.
The least common multiple of 54 , 3 = 54
The Least Common Multiple of 54 and 81 is 162.
The Least Common Multiple of 54 and 126 is 378.
Since 54 is a multiple of 18, it is automatically the LCM.
The Least Common Multiple (LCM) for 54 56 is 1,512.
Least Common Multiple (LCM) for 54 72 is 216
Least Common Multiple (LCM) for 54 135 is 270
The LCM or least common multiple of 36 and 54 is 108.
The Least Common Multiple (LCM) for 36 54 is 108.
Least Common Multiple (LCM) for 54 64 is 1,728
The Least Common Multiple (LCM) for 54 49 is 2,646.