When Peter asked how many times he should forgive his brother, what number did he suggest?

Answer: Seven

Peter suggested up to seven times; Jesus answered that forgiveness must go far beyond seven times.

“Then Peter came to Jesus and asked, “Lord, how many times shall I forgive my brother who sins against me? Up to seven times?” Jesus answered, “I tell you, not just seven times, but seventy-seven times!”— Matthew 18:21-22 (BSB)