221826 has 16 divisors (see below), whose sum is σ = 484128. Its totient is φ = 67200.

The previous prime is 221813. The next prime is 221827. The reversal of 221826 is 628122.

221826 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 221826.

It is not an unprimeable number, because it can be changed into a prime (221827) by changing a digit.

221826 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 (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1615 + ... + 1746.

It is an arithmetic number, because the mean of its divisors is an integer number (30258).

2²²¹⁸²⁶ is an apocalyptic number.

221826 is an abundant number, since it is smaller than the sum of its proper divisors (262302).

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

221826 is a wasteful number, since it uses less digits than its factorization.

221826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3377.

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

The square root of 221826 is about 470.9840761639. The cubic root of 221826 is about 60.5346658330.

Adding to 221826 its reverse (628122), we get a palindrome (849948).

The spelling of 221826 in words is "two hundred twenty-one thousand, eight hundred twenty-six".