822240 has 72 divisors (see below), whose sum is σ = 2810808. Its totient is φ = 218880.

The previous prime is 822233. The next prime is 822253. The reversal of 822240 is 42228.

It is a tau number, because it is divible by the number of its divisors (72).

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

It is a congruent number.

It is an unprimeable number.

822240 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, 1155 + ... + 1725.

It is an arithmetic number, because the mean of its divisors is an integer number (39039).

2⁸²²²⁴⁰ is an apocalyptic number.

822240 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 822240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1405404).

822240 is an abundant number, since it is smaller than the sum of its proper divisors (1988568).

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

822240 is a wasteful number, since it uses less digits than its factorization.

822240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 592 (or 581 counting only the distinct ones).

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

The square root of 822240 is about 906.7745033910. The cubic root of 822240 is about 93.6841671152.

Adding to 822240 its reverse (42228), we get a palindrome (864468).

The spelling of 822240 in words is "eight hundred twenty-two thousand, two hundred forty".