Someone said Lee Sin had more base damage on Ult than Veigar.

Technically, pretty much every AoE ability will have higher base damage than a similar single-target ability.

Anyways, Veigar's ultimate is powerful primarily because it scales with both Veigar's and the target's AP and Veigar can get free AP from his Q.

it is, i've never seen such a thing happen. I don't even have to look it up.

Isn't Veigar's ult mainly powerful due to its dual scaling nature, not its base damage?

But Lee's ult is one of the highest base damage abilities in the game so it could be true.
Looked it up:

At rank 1, Lee's ult is lower than Veigar in terms of BASE DAMAGE, but at ranks 2 and 3 it is higher.

They both also have insane scaling and rather low cooldowns.