Ta có :
\(14^4.4^2.21^5.28^3.18^3\)
\(=\left(7.2\right)^{14}.\left(2^2\right)^2.\left(7.3\right)^5.\left(7.2^2\right)^3.\left(3^2.2\right)^3\)
\(=7^{14}.2^{14}.2^4.7^5.3^5.7^3.2^6.3^6.2^3\)
\(=\left(7^{14}.7^5.7^3\right)\left(2^{14}.2^4.2^6.2^3\right)\left(3^5.3^6\right)\)
\(=7^{22}.2^{27}.3^{11}\)