822021 has 4 divisors (see below), whose sum is σ = 1096032. Its totient is φ = 548012.

The previous prime is 822013. The next prime is 822037. The reversal of 822021 is 120228.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 822021 - 2³ = 822013 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (822011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137001 + ... + 137006.

It is an arithmetic number, because the mean of its divisors is an integer number (274008).

2⁸²²⁰²¹ is an apocalyptic number.

It is an amenable number.

822021 is a deficient number, since it is larger than the sum of its proper divisors (274011).

822021 is a wasteful number, since it uses less digits than its factorization.

822021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274010.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 822021 is about 906.6537376529. The cubic root of 822021 is about 93.6758489216.

Adding to 822021 its reverse (120228), we get a palindrome (942249).

The spelling of 822021 in words is "eight hundred twenty-two thousand, twenty-one".