6691
6691 is a natural number that follows 6690 and precedes 6692. In mathematics, it is a prime number. It is odd and not divisible by 3 or 5, and it has no divisors other than 1 and itself, confirming primality. The digit sum is 22, giving a digital root of 4, and it is congruent to 3 modulo 4 and modulo 8.
In base representations, 6691 is written as 1101000100011 in binary and 0x1A23 in hexadecimal.
As a numerical label, 6691 may appear in catalogs, serial numbers, or identifiers; there is no widely