\(1\times 4^3+3\times 4^2+3\times 4^1+1\times 4^0\)

\(1\times 4^3+3\times 4^2+3\times 4^1+1\times 4^0 = 1\times 64 + 3\times 16 + 3\times 4 + 1\times 1 = 64 + 48 + 12 + 1 = 125\)