The number of KAOS agent Nealis whose identity is adopted by Maxwell Smart when delivering a part of an atomic bomb to its assembly site on Blue Mist Mountain.
The real Agent Nealis has been captured by CONTROL. Although it is established that 127 is the number of the part Nealis is carrying, it appears to be only a lucky guess by Max that it is also Nealis's agent number.
[Episode #24: "Stakeout on Blue Mist Mountain".]