It is estimated

Which one is correct, please?

"It is estimated that the Nuba population numbers 1.1 million."
"It is estimated that the Nuba population numbers around 1.1 million."

It depends on how redundantly redundant you wishbto be.

Both are fine, though the second would be more common, in my experience.

The second one is pretty bad, though passable in speech. Try either

"It is estimated that the Nuba population numbers 1.1 million."

or

"The Nuba population numbers around 1.1 million."

That avoids the repetition.