428

Number
$428$ (four hundred and twenty-eight) is:


 * $2^2 \times 107$


 * The $2$nd integer after $91$ whose square has a decimal representation consisting of the concatenation of $2$ consecutive integers:
 * $428^2 = 183 \, 184$


 * The $1$st integer whose square has a decimal representation consisting of the concatenation of $2$ consecutive increasing integers:
 * $428^2 = 183 \, 184$