The Proto-Indo-European word *pénkʷe
Word *pénkʷe
Meaning five
See also Armenian: hing ‘five’
Proto-Indo-European: *pn̥(kʷ)stí- ‘fist’
Proto-Indo-European: *pn̥kʷtós ‘fifth’
Tocharian A: päñ ‘five’
Avestan: paṇca ‘five, 5’

Comments
Arm. hing/hing/hink, Alb. pesë/pesë, Lith. penki, Ltv. pieci, Gaul. pempe, Gm. fimf/fünf, Eng. fīf/five, Phryg. pinke, Gk. pente, Av. paṇ ča, Ir. cóic/cúig, Kashmiri pā.~tsh, Kamviri puč, Luw. panta, Oscan pompe, ON fimm, Old Prussian pēnkjāi, Osset. fondz/fondz, Pers. panča/panj, OCS pętĭ, Polish pięć, Russ. pjat', Skr. pañca, Toch. päñ/piś, Lat. quinque, Umbrian pumpe, Goth. fimf, Welsh pump

Other words that might be of interest
*hₓok̂tṓ(u) ‘eight’, *trei- ‘three’, *dwoi- ‘group of two, two’, *h₁oinos ‘one’, *kʷetwóres (m), kʷetwesóres (f), kʷetwōr (n) ‘four’, *(h₁)néwn̥ ‘nine’, *sem- ‘one’, *septḿ̥ ‘seven’, *septm̥-k̂ómt-h₂ ‘seventy’, *kswek̂s ‘six’, *tréies (m), trisóres (f), treih₂ (n) tri- [prefix] ‘three’, *dwéh₃(u) ‘two’, *h₁newh₁m̥(h₁néwh₁n̥?) ‘nine’, *tréyes ‘three’, *trī-k̂omt(hₐ) ‘thirty’, *kswek̂s-k̂omt(hₐ) ‘sixty’, *kʷetwóres ‘four’, *per(hₓ)- ‘first’, *dwiyos~dwitos ‘second’, *h₁newh₁m̥m/n̥-mos ‘ninth’, *hₓok̂towós ‘eighth’, *kswek̂sos ‘sixth’, *kʷturyós~kʷetwortos ‘fourth’, *septm̥-mós ‘seventh’, *triyós ‘third’