An example method of assigning a telephone number to a user account in a communications system is provided. The method includes obtaining a mnemonic seed and obtaining a subset of telephone numbers filtered from a global telephone number pool based on the mnemonic seed. The alphanumeric representation of each telephone number in the subset is within a threshold Hamming distance of the mnemonic seed. The method further includes receiving an indication of a selected telephone number from the subset and assigning the selected telephone number to the user account.