Two numbers are heterogeneous if their prime factors are distinct. For example, 
and 
are not heterogeneous since their factors
are each (2, 3).
Heterogeneous Numbers
See also
Distinct Prime Factors, Homogeneous NumbersExplore with Wolfram|Alpha
References
Le Lionnais, F. Les nombres remarquables. Paris: Hermann, p. 146, 1983.Referenced on Wolfram|Alpha
Heterogeneous NumbersCite this as:
Weisstein, Eric W. "Heterogeneous Numbers." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/HeterogeneousNumbers.html