As a consequence, 23 is only a multiple of 1 and 23. Find out more: What is a prime number? Since 23 is a prime number, 23 is also a deficient number, that is to say 23 is a natural integer that is strictly larger than the sum of its proper divisors, i.e., the divisors of 23 without 23 itself (that is 1, by definition!).

