Śrī Rudram is recited in all Śiva temples without exemption; it is a part of all exiting Vedas in various forms. But Śrī Rudra Pāṭha available in Taittirīya saṃhitā (तैत्तिरीयसंहिता) of Kṛṣṇa yajurveda (कृष्णयजुर्वेदः) contains eleven anuvākas (or chapters) followed by Camakaṃ (चमकं) which also consists of eleven anuvākas. The number ‘eleven’ plays a significant role in the Mantras of Śrī Rudram and its chanting by various methods known as Rudraikādaśinī (रुद्रैकादशिनी), Laghurudraṃ (लघुरुद्रं), Mahārudraṃ (महारुद्रं), Atirudraṃ (अतिरुद्रं). Great Sages of yore of our Puṇyabhūmi have skillfully concealed several Mathematical facts in the Vedic mantras; here is an attempt to bring out the significance of ‘eleven’ associated with Śrī Rudram revealing the concept of divisibility concealed in a couple of mantras of it, using Kaṭapaya saṃkhyā paddhati.