rem

Enables the use of the % operator for BigDecimal instances.

inline operator fun BigDecimal.rem(other: BigDecimal): BigDecimal(source)

import java.math.BigDecimal

fun main() {
    val dividend = BigDecimal("10.5")
    val divisor  = BigDecimal("3")

    // Using the % operator, which calls BigDecimal.rem
    val remainder = dividend % divisor

    println("Remainder of $dividend รท $divisor = $remainder")
}

Source