Considering Michael was created by God long before the Universe existed, he would be several billion years old.
If he were alive today he would be about 2000 years old.
If he were still alive today, St. Valentine of Rome would be between 1700 and 1800 years old.
St. Albert Chmielowski was born on August 20, 1845 and died on December 25, 1916. St. Albert Chmielowski would have been 71 years old at the time of death or 169 years old today.
John St Aubyn was born on May 17, 1758 and died on August 10, 1839. John St Aubyn would have been 81 years old at the time of death or 257 years old today.
Emile St. Godard was born on August 15, 1905 and died on March 26, 1948. Emile St. Godard would have been 42 years old at the time of death or 109 years old today.
Mark St. John was born on February 7, 1956 and died on April 5, 2007. Mark St. John would have been 51 years old at the time of death or 59 years old today.
Henry St John was born on September 16, 1678 and died on December 12, 1751. Henry St John would have been 73 years old at the time of death or 336 years old today.
If St. Nicholas of Myra were still alive today he would be about 1700 years old.
It is believed that St. Peter was around 30 years old when he began following Jesus, and he lived until his martyrdom in his 60s or 70s.
St Maximilian Kolbe was born on January 8, 1894 and died on August 14, 1941. This would have been 47 years old at the time of death or 116 years old today.
No, St. Michael is an angel. He is not human so he would not marry.
St. John Richardson Liddell was born on September 6, 1815 and died on February 14, 1870. St. John Richardson Liddell would have been 54 years old at the time of death or 199 years old today.