The most common and most likely answer to this crossword clue is the 13 letter word ARITHMETICIAN
I've seen this crossword clue in The Times
A
R
I
T
H
M
E
T
I
C
I
A
N
More clues leading to the result ARITHMETICIAN
- Tahitian crime out of control — one can work out the figures
- Novel Haitian metric calculator?
- Fresh air and Chianti drinking encountered in summer?
- Certain I am unsure about it, hard I reckon?
- A titchier man, I fancy, may be one who has no trouble with tots!
- Expert on calculating machine trait I engineered
Buddy explains!

The straight part
We know that "one can work out the figures" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one can work out the figures = arithmetician.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ARITHMETICIAN mean?
ARITHMETICIAN noun- One with expertise in arithmetic; a mathematician.