sentences:  Equidigital number
  
  In number theory, an equidigital number is a natural number in a given number base that has the same number of digits as the number of digits in its prime factorization in the given number base, including exponents but excluding exponents equal to 1.For example, in base 10, 1, 2, 3, 5, 7, and 10 (2 · 5) are equidigital numbers .