82440 has 48 divisors (see below), whose sum is σ = 269100. Its totient is φ = 21888.

The previous prime is 82421. The next prime is 82457. The reversal of 82440 is 4428.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 79524 + 2916 = 282^2 + 54^2 .

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

It is a d-powerful number, because it can be written as 8 + 2⁹ + 4⁷ + 4⁸ + 0 .

It is an unprimeable number.

82440 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 246 + ... + 474.

2⁸²⁴⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 82440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134550).

82440 is an abundant number, since it is smaller than the sum of its proper divisors (186660).

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

82440 is a wasteful number, since it uses less digits than its factorization.

82440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246 (or 239 counting only the distinct ones).

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

The square root of 82440 is about 287.1236667361. The cubic root of 82440 is about 43.5223824568.

Adding to 82440 its reverse (4428), we get a palindrome (86868).

The spelling of 82440 in words is "eighty-two thousand, four hundred forty".