3963

3963 is a positive integer. In number theory terms, it factors as 3 × 1321, where 1321 is prime, making 3963 a semiprime (the product of two primes). The sum of its digits is 21, so the number is divisible by 3 but not by 9, and it is odd.

Representations in other bases: in binary it is 111101111011, in octal 7573, and in hexadecimal F7B. In Roman numerals it is MMMCMLXIII, which corresponds to 3000 + 900 + 60 + 3.

Relation to squares: 63^2 equals 3969, so 3963 is 6 less than a square.

Applications and context: as a semiprime, 3963 can serve as a simple example in introductory factorization and base-conversion exercises. It does not have widely known mathematical significance beyond its status as one of many four-digit semiprimes.