Valmiki Ramayana Yuddha Kanda Sarga 28 Shloka 33
Original Shlokaशतंशतसहस्राणांकोटिमाहुर्मनीषिणः । शतंकोटिसहस्राणांशङ्कु: इत्यभिधीयते ।।6.28.33।।
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मनीषिणः the wise men, शतसहस्राणाम् hundred thousand, शतम् hundred, कोटिम् crore, आहुः multiplied by, कोटिसहस्राणाम् thousand crores, शतम् hundred, शङ्कुः Sankhu, इति thus, अभिधीयते is said to be.
"It is said by wise men that hundred thousand crores multiplied by hundred thousand crores as Sankha."