Table:
text: Peruvian general election, 2006
Congress
Congress
Electoral_District Registered_voters Seats_in_Congress Candidates_per_party Participating_parties Total_candidates
Amazonas 179331 2 3 17 47
Ancash 611881 5 5 21 99
Apurímac 195954 2 3 21 55
Arequipa 770535 5 5 21 101
Ayacucho 306662 3 3 20 58
Cajamarca 721239 5 5 23 109
Callao 541730 4 4 24 92
Cusco 643629 5 5 22 98
Huancavelica 203844 2 3 15 39
Huánuco 354416 3 3 22 65
Ica 451197 4 5 22 88
Junín 701190 5 5 22 99
La Libertad 942656 7 7 22 145
Lambayeque 676735 5 5 22 101
Lima 6063109 35 35 24 738
Loreto 416419 3 3 22 60

Question: What was the number of parties participating in the Peruvian general elections of 2006, when a total of 643629 registered voters were registered?