442221 has 32 divisors (see below), whose sum is σ = 725760. Its totient is φ = 236544.

The previous prime is 442217. The next prime is 442229. The reversal of 442221 is 122244.

It is not a de Polignac number, because 442221 - 2² = 442217 is a prime.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 442221.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 442221.

It is not an unprimeable number, because it can be changed into a prime (442229) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15235 + ... + 15263.

It is an arithmetic number, because the mean of its divisors is an integer number (22680).

2⁴⁴²²²¹ is an apocalyptic number.

It is an amenable number.

442221 is a deficient number, since it is larger than the sum of its proper divisors (283539).

442221 is a wasteful number, since it uses less digits than its factorization.

442221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85.

The product of its digits is 128, while the sum is 15.

The square root of 442221 is about 664.9969924744. The cubic root of 442221 is about 76.1868096016.

Adding to 442221 its reverse (122244), we get a palindrome (564465).

The spelling of 442221 in words is "four hundred forty-two thousand, two hundred twenty-one", and thus it is an iban number.