25

is the integer between and.

Math features

 * 25 is an odd number.
 * 25 is a deficient number. Its factors add up to 7.
 * 25 is a square number.
 * 25 is a Friedman number, like all powers of 5, being equal to 52.
 * 25 is a factor of 100.
 * 25 is one of the only three (the others are 0 and 26) numbers whose factorial divided by the number to the power of 10 is less than 10 but more than 1, and $$\frac{25!}{10^{25}}=1.5511210043330985984$$. Due to this, 26! will work.