The Hindu rosary or set of mantra counting has 108 beads. 108 has been a sacred number in the Indian Subcontinent for a very long time. This number is explained in many different ways.
The ancient Indians were excellent mathematicians and 108 may be the product of a precise mathematical operation (e.g. 1 power 1 x 2 power 2 x 3 power 3 = 108) which was thought to have special numerological significance.
Powers of 1, 2, and 3 in math: 1 to 1st power=1; 2 to 2nd power=4 (2x2); 3 to 3rd power=27 (3x3x3). 1x4x27=108
Sanskrit alphabet: There are 54 letters in the Sanskrit alphabet. Each has masculine and feminine, shiva and shakti. 54 times 2 is 108.
Sri Yantra: On the Sri Yantra there are marmas where three lines intersect, and there are 54 such intersections. Each intersections has masculine and feminine, shiva and shakti qualities. 54 x 2 equals 108. Thus, there are 108 points that define the Sri Yantra as well as the human body.
9 times 12: Both of these numbers have been said to have spiritual significance in many traditions. 9 times 12 is 108. Also, 1 plus 8 equals 9. That 9 times 12 equals 108.
Heart Chakra: The chakras are the intersections of energy lines, and there are said to be a total of 108 energy lines converging to form the heart chakra. One of them, sushumna leads to the crown chakra, and is said to be the path to Self-realization.
Marmas: Marmas or marmastanas are like energy intersections called chakras, except have fewer energy lines converging to form them. There are said to be 108 marmas in the subtle body.
Time: Some say there are 108 feelings, with 36 related to the past, 36 related to the present, and 36 related to the future.
Astrology: There are 12 constellations, and 9 arc segments called namshas or chandrakalas. 9 times 12 equals 108. Chandra is moon, and kalas are the divisions within a whole.
Planets and Houses: In astrology, there are 12 houses and 9 planets. 12 times 9 equals 108.
Gopis of Krishna: In the Krishna tradition, there were said to be 108 gopis.
1, 0, and 8: 1 stands for God or higher Truth, 0 stands for emptiness or completeness in spiritual practice, and 8 stands for infinity or eternity.
Sun and Earth: The diameter of the sun is 108 times the diameter of the Earth.
Numerical scale: The 1 of 108, and the 8 of 108, when added together equals 9, which is the number of the numerical scale, i.e. 1, 2, 3 ... 10, etc., where 0 is not a number.