84240 has 100 divisors (see below), whose sum is σ = 315084. Its totient is φ = 20736.

The previous prime is 84239. The next prime is 84247. The reversal of 84240 is 4248.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20736 + 63504 = 144^2 + 252^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6474 + ... + 6486.

2⁸⁴²⁴⁰ is an apocalyptic number.

84240 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 84240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (157542).

84240 is an abundant number, since it is smaller than the sum of its proper divisors (230844).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

84240 is a wasteful number, since it uses less digits than its factorization.

84240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38 (or 23 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 84240 is about 290.2412789387. The cubic root of 84240 is about 43.8368614444.

Adding to 84240 its reverse (4248), we get a palindrome (88488).

It can be divided in two parts, 84 and 240, that added together give a square (324 = 18²).

The spelling of 84240 in words is "eighty-four thousand, two hundred forty".