The sequence "1, 2, 139" consists of three numbers. The first two numbers, 1 and 2, are the first two natural numbers, often used in counting and basic arithmetic. They represent the foundation of mathematics and are essential in various mathematical operations. The number 139 is a prime number, meaning it can only be divided by 1 and itself without resulting in a fraction. It is also an odd number and falls between 138 and 140 in the number line. Prime numbers like 139 play a crucial role in number theory and cryptography.