 Multiplying an integer by its formula_20-adic absolute value cancels out the factors of formula_20 in its factorization, leaving only the other primes.Just as the distance between two real numbers can be measured by the absolute value of their distance, the distance between two rational numbers can be measured by their formula_20-adic distance, the formula_20-adic absolute value of their difference.For this definition of distance, two numbers are close together (they have a small distance) when their difference is divisible by a high power of formula_20.