3721

3721 is a natural number, following 3720 and preceding 3722. It is the square of 61, i.e., 61^2, making it a perfect square.

3721 = 61^2; since 61 is prime, its divisors are 1, 61, and 3721; thus it has exactly three positive divisors. It is odd and composite. It is congruent to 1 modulo 4 and modulo 8; specifically 3721 ≡ 1 (mod 4) and 3721 ≡ 1 (mod 8). It is not divisible by 3 or 5.

Digits sum to 13, giving a digital root of 4. In base representations, 3721 appears as binary 111010001001, hex 0xE89, and octal 7211. In Roman numerals it is written as MMM DCCXXI, and in words it reads three thousand seven hundred twenty-one.

In mathematics, 3721 is noted as the square of a prime number, 61, which makes it a simple example of a perfect square with a prime root. Its prime factorization is 61^2, and its positive divisors are 1, 61, and 3721. Aside from these arithmetic properties, 3721 does not have widely recognized special significance in other standard mathematical contexts.