Encode any integer to string base of choice. Just replace keys with one you want to encode into. StringBase.encode(11111111) == "frgh"

string_base.rb

module StringBase
  KEYS = 'bcdfghjklmnpqrstvwxyz'

  def self.encode( value )
    ring = Hash[KEYS.chars.map.with_index.to_a.map(&:reverse)]
    base = KEYS.length
    result = []
    until value == 0
      result << ring[ value % base ]
      value /= base
    end
    result.reverse.join
  end

  def self.decode( string )
    ring = Hash[KEYS.chars.map.with_index.to_a]
    base = KEYS.length
    # Ruby < 2 string.reverse.chars.with_index.inject(0) do |sum,(char,i)|
    string.reverse.chars.map.with_index.inject(0) do |sum,(char,i)|
      sum + ring[char] * (base**i)
    end
  end
end