442421 has 6 divisors (see below), whose sum is σ = 514710. Its totient is φ = 379176.

The previous prime is 442399. The next prime is 442439. The reversal of 442421 is 124244.

It can be written as a sum of positive squares in only one way, i.e., 442225 + 196 = 665^2 + 14^2 .

It is a de Polignac number, because none of the positive numbers 2^k-442421 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 442421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442121) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4466 + ... + 4563.

It is an arithmetic number, because the mean of its divisors is an integer number (85785).

2⁴⁴²⁴²¹ is an apocalyptic number.

It is an amenable number.

442421 is a deficient number, since it is larger than the sum of its proper divisors (72289).

442421 is an equidigital number, since it uses as much as digits as its factorization.

442421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9043 (or 9036 counting only the distinct ones).

The product of its digits is 256, while the sum is 17.

The square root of 442421 is about 665.1473520958. The cubic root of 442421 is about 76.1982933510.

Adding to 442421 its reverse (124244), we get a palindrome (566665).

The spelling of 442421 in words is "four hundred forty-two thousand, four hundred twenty-one", and thus it is an iban number.