sentences:  Frugal number
  
  In number theory, a frugal number is a natural number in a given number base that has more digits than the number of digits in its prime factorization in the given number base (including exponents).For example, in base 10, 125 = 53, 128 = 27, 243 = 35, and 256 = 28 are frugal numbers , and in base 2, thirty-two is a frugal number, since 100000 = 10101.