21 in Decimal
Hexadecimal 21 equals 33 in decimal.
21 in all number bases
Decimal33
Hexadecimal0x21
Binary0010 0001
Octal41
How 21 converts from hexadecimal to decimal
Multiply each digit by 16 raised to its position (starting at 0 from the right), then add the results:
2× 161 = 2 × 16 = 32
1× 160 = 1 × 1 = 1
Sum: 33