It could be either depending on what year it's in and what rule is used to determine Week 1.
23 is an odd number.
23 is an odd number.
23 is odd. A sum of two even numbers never makes an odd number. Likewise, no sum of two odd numbers makes an odd number. 23 can only be made by adding an odd and an even number.
23 April 1958 was a Wednesday.
April 23, 1963 was a Tuesday.
April 23, 1987 was a Thursday.
23 April 1957 was a Tuesday.
April 23 2010 was a Friday.
April 23, 1974 was a Tuesday.
April 23, 1940, was a Tuesday.
April 23, 1961 fell on a Sunday.
April 23, 1616 fell on a Tuesday.