442621 has 4 divisors (see below), whose sum is σ = 446652. Its totient is φ = 438592.

The previous prime is 442619. The next prime is 442633. The reversal of 442621 is 126244.

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 152100 + 290521 = 390^2 + 539^2 .

It is a cyclic number.

It is not a de Polignac number, because 442621 - 2¹ = 442619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442601) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1846 + ... + 2071.

It is an arithmetic number, because the mean of its divisors is an integer number (111663).

2⁴⁴²⁶²¹ is an apocalyptic number.

It is an amenable number.

442621 is a deficient number, since it is larger than the sum of its proper divisors (4031).

442621 is a wasteful number, since it uses less digits than its factorization.

442621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4030.

The product of its digits is 384, while the sum is 19.

The square root of 442621 is about 665.2976777353. The cubic root of 442621 is about 76.2097736400.

Adding to 442621 its reverse (126244), we get a palindrome (568865).

The spelling of 442621 in words is "four hundred forty-two thousand, six hundred twenty-one".