Calls to the number were greeted by a long beep sound.
Dikshit had last week announced launch of the round-the-clock helpline for offering help to women in distress amid nationwide uproar over the December 16 brutal gang-rape of the 23-year-old in the national capital.
The girl had breathed her last on Saturday in a Singapore hospital.
Senior Delhi government officials
They said the helpline, which will operate from the Chief Minister's Office in Delhi Secretariat, can be contacted from landlines as well as mobile phones.
The telecom ministry had last week released the three-digit number following a request by Dikshit. It will be the first three-digit number to have been allotted by the ministry in two years.
The ministry had earlier allotted '167' for the helpline but upon request for a number that would be easier to remember, the number was changed to '181'.
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