tatra rājanya-kanyānāḿ
ṣaṭ-sahasrādhikāyutam
bhaumāhṛtānāḿ vikramya
rājabhyo dadṛśe hariḥ
tatra -- there; rajanya -- of the royal order; kanyanam -- of maidens; shat-sahasra -- six thousand; adhika -- more than; ayutam -- ten thousand; bhauma -- by Bhauma; ahritanam -- taken; vikramya -- by force; rajabhyah -- from kings; dadrise -- saw; harih -- Lord Krishna.
There Lord Krishna saw sixteen thousand royal maidens, whom Bhauma had taken by force from various kings.
Srila Sridhara Svami provides evidence from the sage Parasara, as quoted in the Vishnu Purana (5.29.31), to the effect that there were actually 16,100 royal maidens imprisoned in Bhauma's palace:
kanya-pure sa kanyanam
shodasatulya-vikramah
satadhikani dadrise
sahasrani maha-mate
"Within the maidens' quarters, O wise one, that Lord of unequaled prowess found 16,100 princesses."
Another relevant verse from the Vishnu Purana (5.29.9) is as follows:
deva-siddhasuradinam
nripanam ca janardana
hritva hi so 'surah kanya
rurodha nija-mandire
"The demon [Bhaumasura] kidnapped the unmarried daughters of demigods, siddhas, asuras and kings, O Janardana, and imprisoned them in his palace."
