822564 has 36 divisors (see below), whose sum is σ = 2114476. Its totient is φ = 269568.

The previous prime is 822557. The next prime is 822571. The reversal of 822564 is 465228.

It is an interprime number because it is at equal distance from previous prime (822557) and next prime (822571).

It can be written as a sum of positive squares in 2 ways, for example, as 166464 + 656100 = 408^2 + 810^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×822564² = 1353223068192, which contains 22 as substring.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2472 + ... + 2784.

2⁸²²⁵⁶⁴ 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 822564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1057238).

822564 is an abundant number, since it is smaller than the sum of its proper divisors (1291912).

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

822564 is a wasteful number, since it uses less digits than its factorization.

822564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396 (or 391 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

The square root of 822564 is about 906.9531410167. The cubic root of 822564 is about 93.6964707751.

The spelling of 822564 in words is "eight hundred twenty-two thousand, five hundred sixty-four".