145

is the integer between.

Math features
$$145 = 1! + 4! + 5!$$
 * 145 is an odd number.
 * 145 can be expressed as a sum of its digits' factorials. Thus it is a factorion.
 * 145 is a deficient number.
 * 145 is a square-free number.
 * 145 is a composite number.