{BN.* 123456789123456789123456789 123456789123456789123456789}
-> 15241578780673678546105778281054720515622620750190521

to be compared with the "standard" lambdatalk builtin * operator

{* 123456789123456789123456789 123456789123456789123456789}
-> 1.524157878067368e+52