Repeated numbers refer to instances where the same digit appears multiple times within a number. For example, in the number 1223, the digit 2 is repeated. This concept is often observed in various contexts, such as in phone numbers, license plates, or even in mathematical sequences. In mathematics, repeated numbers can be significant in statistics and probability. For instance, when analyzing data sets, the frequency of repeated numbers can indicate trends or patterns. Understanding repeated numbers can also be useful in fields like cryptography, where patterns may affect security measures.