Number twister

n = abcde, a 5digits number (a,b,c,d,e represent the digits).
When multiplied by 4, the result = edcba (digits reversed).

What is, praytell, abcde?

5am?...watching the Raonic-Murray tennis match!

21978 x 4 = 87912

Yepper!

21(n 9's)78 * 4 = 87(n 9's)12 ; n = as many 9's as you want!

Similarly with:
10(n 9's)89 * 9 = 98(n 9's)01