822121 has 4 divisors (see below), whose sum is σ = 850500. Its totient is φ = 793744.

The previous prime is 822113. The next prime is 822131. The reversal of 822121 is 121228.

822121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 190096 + 632025 = 436^2 + 795^2 .

It is a cyclic number.

It is not a de Polignac number, because 822121 - 2³ = 822113 is a prime.

It is a Duffinian number.

822121 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 822095 and 822104.

It is not an unprimeable number, because it can be changed into a prime (822131) 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, 14146 + ... + 14203.

It is an arithmetic number, because the mean of its divisors is an integer number (212625).

2⁸²²¹²¹ is an apocalyptic number.

It is an amenable number.

822121 is a deficient number, since it is larger than the sum of its proper divisors (28379).

822121 is a wasteful number, since it uses less digits than its factorization.

822121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28378.

The product of its digits is 64, while the sum is 16.

The square root of 822121 is about 906.7088838210. The cubic root of 822121 is about 93.6796473668.

Adding to 822121 its reverse (121228), we get a palindrome (943349).

The spelling of 822121 in words is "eight hundred twenty-two thousand, one hundred twenty-one".