821226 has 16 divisors (see below), whose sum is σ = 1877184. Its totient is φ = 234624.

The previous prime is 821209. The next prime is 821263. The reversal of 821226 is 622128.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

821226 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9735 + ... + 9818.

It is an arithmetic number, because the mean of its divisors is an integer number (117324).

2⁸²¹²²⁶ is an apocalyptic number.

821226 is an abundant number, since it is smaller than the sum of its proper divisors (1055958).

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

821226 is a wasteful number, since it uses less digits than its factorization.

821226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19565.

The product of its digits is 384, while the sum is 21.

The square root of 821226 is about 906.2152062286. The cubic root of 821226 is about 93.6456403175.

It can be divided in two parts, 82122 and 6, that added together give a palindrome (82128).

The spelling of 821226 in words is "eight hundred twenty-one thousand, two hundred twenty-six".