5. Now arrange for 7 students to participate in 5 sports events, requiring that students A and B cannot participate in the same event, each event must have participants, and each person can only participate in one event. The number of different arrangements that meet the above requirements is $\qquad$ . (Answer in numbers)
According to the problem, the number of participants in each sports event is $2,2,1,1,1$ or $3,1,1,1,1$.
When the number of participants in each sports event is $2,2,1,1,1$, the number of different arrangement schemes is $\frac{C_{7}^{2} \cdot C_{5}^{2}}{2!} \cdot A_{5}^{5}$, at this time, the number of arrangement schemes where students A and B participate in the same event is $C_{5}^{2} \cdot A_{5}^{5}$; when the number of participants in each sports event is $3,1,1,1,1$, the number of different arrangement schemes is $C_{7}^{3} \cdot A_{5}^{5}$, at this time, the number of arrangement schemes where students A and B participate in the same event is $C_{5}^{1} \cdot A_{5}^{5}$. Therefore, the number of different arrangement schemes that meet the requirements is $\left(\frac{C_{7}^{2} \cdot C_{5}^{2}}{2!}-C_{5}^{2}+C_{7}^{3}-C_{5}^{1}\right) A_{5}^{5}=15000$.