n = gets.chomp.to_i

require 'prime'

class Integer
  def my_divisor_list
    divisors = [1]
    primes = []
    Prime.prime_division(self).each do |prime|
      prime[1].times {primes << prime[0]}
    end

    1.upto(primes.size) do |i|
      primes.combination(i) do |prime|
        divisors << prime.inject{|a,b| a *= b}
      end
    end

    divisors.uniq!
    divisors.sort!
    return divisors
  rescue ZeroDivisionError
    return
  end
end

ans = []
n.my_divisor_list.uniq.each do |i|
  s, a = n.divmod(i)
  if a == 0
    ans.push(s-1 + i-1)
  end
end
p ans.min