253 (number)

253 (two hundred [and] fifty-three) is the natural number following 252 and preceding 254.

In mathematics

253 is:

• a semiprime since it is the product of 2 primes.
• a brilliant number, meaning that its prime factors have the same amount of digits
• the 22nd triangular number.
• a star number.
• a centered heptagonal number.
• a centered nonagonal number.
• a Blum integer.
• a member of the 13-aliquot tree.

References