Il numero romano MMCM nel sistema decimale vale: 2900.
MMCM in latino si scrive duo milia nongenti,
mentre in italiano duemilanovecento.
MMDCCCLXXXI, MMDCCCLXXXII, MMDCCCLXXXIII, MMDCCCLXXXIV, MMDCCCLXXXV, MMDCCCLXXXVI, MMDCCCLXXXVII, MMDCCCLXXXVIII, MMDCCCLXXXIX, MMDCCCXC, MMDCCCXCI, MMDCCCXCII, MMDCCCXCIII, MMDCCCXCIV, MMDCCCXCV, MMDCCCXCVI, MMDCCCXCVII, MMDCCCXCVIII, MMDCCCXCIX, MMCMI, MMCMII, MMCMIII, MMCMIV, MMCMV, MMCMVI, MMCMVII, MMCMVIII, MMCMIX, MMCMX, MMCMXI, MMCMXII, MMCMXIII, MMCMXIV, MMCMXV, MMCMXVI, MMCMXVII, MMCMXVIII, MMCMXIX