99 (number)

99 (ninety-nine) is the natural number following 98 and preceding 100.

In mathematics
99 is:
 * a composite number; a square-prime, of the form (p2, q). It is the 11th composite number of this form and the third of the form (32, q). It has an aliquot sum of 57, within an aliquot sequence of two composite numbers (99,57,23,1,0), to the Prime in the 23-aliquot tree.
 * a Kaprekar number
 * a lucky number
 * a palindromic number
 * the ninth repdigit
 * the sum of the cubes of three consecutive integers: 99 = 23 + 33 + 43
 * the sum of the sums of the divisors of the first 11 positive integers.
 * the highest two digit number in decimal.

In music

 * "99", a song by the band Toto on the Hydra album.
 * "99 Bottles of Beer", a counting song.
 * "99 Luftballons", a German-language song by the band Nena.
 * "99 Problems", a song by Jay-Z on The Black Album.
 * "99 Ways to Die", a song by Megadeth on the Hidden Treasures EP.

In religion

 * In Abrahamic religions, 99 refers to the age at which Abram was renamed Abraham, as accounted by Genesis 17.
 * In Christianity, 99 also refers to the number of sheep a shepherd central to the Parable of the Lost Sheep risks leaving unguarded to find one lost sheep.
 * In Islam, 99 is the number of total names for Allah.

In other fields

 * The atomic number of einsteinium, an actinide.
 * ".99" is frequently used as a price ender in pricing.
 * 99, the jersey number of Wayne Gretzky, since permanently retired