91 (sayı)
Also known as ninety one, ninety-one
natural number
AI overview
91 is a natural number that comes after 90 and before 92. It's notable because despite appearing to be prime at first glance, it's actually composite—equal to 7 multiplied by 13—making it a classic example used to illustrate that not all odd numbers are prime.
AI-generated from the Wikipedia summary — may contain errors.