In Indian number culture the auspicious numbers are 108, 9 and 7, and the one people handle carefully is 8. None of them work the way Chinese lucky numbers work. There is no pun underneath. Sanskrit hands you a count rather than a homophone for prosperity. A japa mala carries 108 beads, the Muktikā canon lists 108 Upanishads, the Sri Vaishnava tradition reveres 108 Divya Desams, and a Hindu wedding is finished at the seventh step. These numbers are auspicious because of what has been counted with them.
The arithmetic most often given for 108 is astrological: nine grahas multiplied by twelve rāśis. Other traditions reach the same total by a different route. Buddhist teaching counts 108 kleshas, the afflictions a practitioner works to end, and Tibetan malas keep the bead count for that reason. Jain and Sikh practice use malas of 108 as well. Nine is fixed by the navagraha, the nine celestial bodies of Hindu astrology, each with its own day, colour and shrine. Seven is fixed by the saptapadi, the seven steps a couple takes together around the fire.
How much of this is conviction depends entirely on who you ask. A priest fixing a wedding muhurta is working from a calculation. A family sealing a gift envelope at ₹101 is following a custom whose reason most people can state and few would defend as physics. Urban India then stacks a second set of habits on top: hotels skipping the thirteenth floor for foreign guests, buyers hunting a registration number that adds to a favourable digit. Plenty of Indians observe all of it and believe none of it, which is a perfectly normal way to live inside a tradition.