In traditional Numerology twelve would be 1+2 = 3 which is a powerful number in its own right.  For more about 3 SEE HERE.  But 12 appears in many other traditions throughout history as well.

The Power of Twelve

Twelve is the number of the disciples accompanying the great Masters of history:

Jesus and the 12 apostles;

the 12 disciples choose by Mahomet to spread his doctrine;

the 12 minor flamines beside the Pontiff Maximus;

the 12 first companions of St. Francis of Assisi;

the 12 disciples of Confucius;

the 12 disciples of Mithra;

the 12 descendants of Ali;

the 12 companions of Odin, with also the 12 goddesses for women;

the 12 marshals of Napoleon;

the twelve principal divinities in the Greek mythology;

the twelve names of the Sun in Sanskrit, which are pronounced such as the mantras,

the number of proposals or verses of the Emerald Table, summarising all the teaching of the Hermetic tradition. (This is a document originating from Egypt, attributed to Hermes Trismegist);

the human gestation period is 12 luna months;

the human cell has twelve biochemical salts;

the 12 colours of creation (pure light is made up, of 12 colours white light is made of 7).

What Twelve Relates to

12 relates to completion. It represents the completed cycle of experience and when an individual reincarnates as a number 12 they have completed a full cycle of experience and learned of the possibility of regeneration toward a higher consciousness. They belong to a group of developed souls who have accumulated an unusual inner strength through many and varied lifetimes. They may still, however, be hindered by old habits that need to be changed. The soul then attracts what it needs as a learning experience. A reversal of negative thoughts can bring about very favourable and positive effects, and can aid in achieving their goals and aspirations.

Number 12 warns of the necessity to be alert to every situation, to be suspicious of those who offer a high position and carefully analyse it, and to be aware of false flattery and those who use it to gain their own ends. Number 12 represents the educational process on all levels, the submission of the will required and the sacrifice necessary to achieve knowledge and wisdom on both Spiritual and Intellectual levels. When the intellect is sacrificed to the feelings, the mind will be illuminated with the answers it seeks. Attention paid to requirements of education will end suffering and bring success. 12 is about freedom. So whether you were born a 12 or not the 12 has been influencing us all and will continue to do so.

In the Gregorian Calendar December is the 12 month and is a month of 'letting go of the old' and 'looking ahead to the new'. This can be on both small and large scales, and it can/will affect all facets of life including family relations, partnerships, financials, careers and the like. If anything has been bothering you these last few weeks (months, years …), So the twelth month is a time for bringing the aspirtations of the year to a close.  A 12 year is a great time to deal with the issues of the last few years and be done with them once and for all, to let go of any fear that may have been ruling you for so long and create a better and brighter for yourself and thus us all.

The Individual numerical vibrations of 12

12th also hold the vibrations of the numbers 1, 2 and 3 individually and collectively.

Briefly 1 is the vibration of ‘new beginnings’ and starting things afresh.

The 2 vibration is about seeking 'balance' and that's certainly something that many will struggle with - balancing the spiritual, emotional mental and physical, the masculine and feminine within, work life balance, let alone balancing the bank balance, balancing in every way. The 2 energy also signifies the coming together of loved ones, relationships and family. 2 energy also encourages us to tune into our emotional side and to express our feelings. 2 energy encourages 'love'.

3 is to do with communications and expressing ourselves on all levels, of being honest with ourselves and others. In this time of change we need to believe in our higher selves in express that self in simple and constructive ways.

2012 and the Mayan Calander

12.12.12 in traditional numerology = 333 = 9 the number of completion. This is the same for 21.12.12 which according to Mayan texts and other shamanistic traditions around the world was the beginning of the next cycle of life. 

In fact 21.12.2012 = 11 which is also a master number, (SEE HERE for more about 11) and if you think about what has been happening in your life and the world since then you can see how this powerful combination has been at work.  I can certainly see it in my own life.