Professional philosophers seem to be similarly split, according to a survey[1].
It seems to me like one of those cases where one's opinion is strongly influenced by raw intuition.
Assuming numbers are just a construct of our minds, we could even argue that unicorns have more existence than numbers. We can’t proof a unicorn doesn’t exist. So there is a probability of its existence greater than zero. As numbers are only constructed, we’re sure they don’t exist and this shows that unicorns have more existence than numbers.