SB 9.6.22
yah priyartham utankasya
dhundhu-namasuram bali
sutanam eka-vimsatya
sahasrair ahanad vrtah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
To satisfy the sage Utanka, the greatly powerful Kuvalayasva killed a demon named Dhundhu. He did this with the assistance of his twenty-one thousand sons.