822440 has 32 divisors (see below), whose sum is σ = 1917000. Its totient is φ = 317184.

The previous prime is 822433. The next prime is 822517. The reversal of 822440 is 44228.

It can be written as a sum of positive squares in 4 ways, for example, as 515524 + 306916 = 718^2 + 554^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 806 + ... + 1514.

2⁸²²⁴⁴⁰ 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 822440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (958500).

822440 is an abundant number, since it is smaller than the sum of its proper divisors (1094560).

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

822440 is a wasteful number, since it uses less digits than its factorization.

822440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 749 (or 745 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 822440 is about 906.8847776868. The cubic root of 822440 is about 93.6917623487.

Adding to 822440 its reverse (44228), we get a palindrome (866668).

The spelling of 822440 in words is "eight hundred twenty-two thousand, four hundred forty".