Hikutini previously spent time with the 49ers (2017-18), Vikings (2018-19) and Cowboys (2019-21). Dallas released Hikutini earlier this month.
He has appeared in four NFL games – all in 2017 with the 49ers – and has two career catches for 15 yards.
Kalu and Milton join Logan Ryan and Adoree’ Jackson as former members of the Titans’ secondary who have recently signed with the Giants.
Kalu has played all 28 of his career games with Tennessee, including a season-high 15 in 2020.
The Titans originally signed him as a rookie free agent out of Nebraska following the 2018 draft.
Milton has appeared in 55 career games with one start and has recovered two fumbles. He spent his first three seasons with the Colts before signing with the Titans in 2019.
He also has appeared in two postseason contests, both with the Colts in 2018. He forced a fumble on a Tyreek Hill punt return in a 2018 divisional round loss to the Chiefs.