13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13
13+13+13+13+13+13+13+13+13+13 = 13 * 10 = 130.
It is 13.It is 13.It is 13.It is 13.
13 - (-13) = 13 + 13 = 26
If its a square, its 13+13+13+13 which equals 52.
The answer would be 6,561. 38 = 6,561
91
28
There have been 135 Friday the 13ths including both 1934 and 2012 as follows:Friday 13 April 1934Friday 13 July 1934Friday 13 September 1935Friday 13 December 1935Friday 13 March 1936Friday 13 November 1936Friday 13 August 1937Friday 13 May 1938Friday 13 January 1939Friday 13 October 1939Friday 13 September 1940Friday 13 December 1940Friday 13 June 1941Friday 13 February 1942Friday 13 March 1942Friday 13 November 1942Friday 13 August 1943Friday 13 October 1944Friday 13 April 1945Friday 13 July 1945Friday 13 September 1946Friday 13 December 1946Friday 13 June 1947Friday 13 February 1948Friday 13 August 1948Friday 13 May 1949Friday 13 January 1950Friday 13 October 1950Friday 13 April 1951Friday 13 July 1951Friday 13 June 1952Friday 13 February 1953Friday 13 March 1953Friday 13 November 1953Friday 13 August 1954Friday 13 May 1955Friday 13 January 1956Friday 13 April 1956Friday 13 July 1956Friday 13 September 1957Friday 13 December 1957Friday 13 June 1958Friday 13 February 1959Friday 13 March 1959Friday 13 November 1959Friday 13 May 1960Friday 13 January 1961Friday 13 October 1961Friday 13 April 1962Friday 13 July 1962Friday 13 September 1963Friday 13 December 1963Friday 13 March 1964Friday 13 November 1964Friday 13 August 1965Friday 13 May 1966Friday 13 January 1967Friday 13 October 1967Friday 13 September 1968Friday 13 December 1968Friday 13 June 1969Friday 13 February 1970Friday 13 March 1970Friday 13 November 1970Friday 13 August 1971Friday 13 October 1972Friday 13 April 1973Friday 13 July 1973Friday 13 September 1974Friday 13 December 1974Friday 13 June 1975Friday 13 February 1976Friday 13 August 1976Friday 13 May 1977Friday 13 January 1978Friday 13 October 1978Friday 13 April 1979Friday 13 July 1979Friday 13 June 1980Friday 13 February 1981Friday 13 March 1981Friday 13 November 1981Friday 13 August 1982Friday 13 May 1983Friday 13 January 1984Friday 13 April 1984Friday 13 July 1984Friday 13 September 1985Friday 13 December 1985Friday 13 June 1986Friday 13 February 1987Friday 13 March 1987Friday 13 November 1987Friday 13 May 1988Friday 13 January 1989Friday 13 October 1989Friday 13 April 1990Friday 13 July 1990Friday 13 September 1991Friday 13 December 1991Friday 13 March 1992Friday 13 November 1992Friday 13 August 1993Friday 13 May 1994Friday 13 January 1995Friday 13 October 1995Friday 13 September 1996Friday 13 December 1996Friday 13 June 1997Friday 13 February 1998Friday 13 March 1998Friday 13 November 1998Friday 13 August 1999Friday 13 October 2000Friday 13 April 2001Friday 13 July 2001Friday 13 September 2002Friday 13 December 2002Friday 13 June 2003Friday 13 February 2004Friday 13 August 2004Friday 13 May 2005Friday 13 January 2006Friday 13 October 2006Friday 13 April 2007Friday 13 July 2007Friday 13 June 2008Friday 13 February 2009Friday 13 March 2009Friday 13 November 2009Friday 13 August 2010Friday 13 May 2011Friday 13 January 2012Friday 13 April 2012Friday 13 July 2012
From 1970 to 2014 there were 77 Friday the 13ths as follows:Friday 13 February 1970Friday 13 March 1970Friday 13 November 1970Friday 13 August 1971Friday 13 October 1972Friday 13 April 1973Friday 13 July 1973Friday 13 September 1974Friday 13 December 1974Friday 13 June 1975Friday 13 February 1976Friday 13 August 1976Friday 13 May 1977Friday 13 January 1978Friday 13 October 1978Friday 13 April 1979Friday 13 July 1979Friday 13 June 1980Friday 13 February 1981Friday 13 March 1981Friday 13 November 1981Friday 13 August 1982Friday 13 May 1983Friday 13 January 1984Friday 13 April 1984Friday 13 July 1984Friday 13 September 1985Friday 13 December 1985Friday 13 June 1986Friday 13 February 1987Friday 13 March 1987Friday 13 November 1987Friday 13 May 1988Friday 13 January 1989Friday 13 October 1989Friday 13 April 1990Friday 13 July 1990Friday 13 September 1991Friday 13 December 1991Friday 13 March 1992Friday 13 November 1992Friday 13 August 1993Friday 13 May 1994Friday 13 January 1995Friday 13 October 1995Friday 13 September 1996Friday 13 December 1996Friday 13 June 1997Friday 13 February 1998Friday 13 March 1998Friday 13 November 1998Friday 13 August 1999Friday 13 October 2000Friday 13 April 2001Friday 13 July 2001Friday 13 September 2002Friday 13 December 2002Friday 13 June 2003Friday 13 February 2004Friday 13 August 2004Friday 13 May 2005Friday 13 January 2006Friday 13 October 2006Friday 13 April 2007Friday 13 July 2007Friday 13 June 2008Friday 13 February 2009Friday 13 March 2009Friday 13 November 2009Friday 13 August 2010Friday 13 May 2011Friday 13 January 2012Friday 13 April 2012Friday 13 July 2012Friday 13 September 2013Friday 13 December 2013Friday 13 June 2014
13 x 13 x 13 = 2197
13 x 13 x 13 is equal to 2,197