1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 y
1 Y (yotta) is equal to 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 y (yocto). To convert from yotta to yocto, multiply by 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 or divide by 0.000000000000000000000000000000000000000000000001.