Valmiki Ramayana Kishkindha Kanda Sarga 37 Shloka 21

यत्र wherever, अर्कः Sun, अस्तं गच्छति sets, तस्मिन् in that, गिरिवरे in the best of mountains, स्थिताः staying at, सन्तप्तहेममहाभास shining like pure molten gold, दश कोट्यः ten crores, तस्मात् from there, च्युताः moved out.

Ten crores of monkeys shining like pure molten gold, staying on the best of mountains where the Sun sets moved towards Kishkinda.