442522021 has 4 divisors (see below), whose sum is σ = 442604844. Its totient is φ = 442439200.

The previous prime is 442522009. The next prime is 442522033. The reversal of 442522021 is 120225244.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (442522009) and next prime (442522033).

It can be written as a sum of positive squares in 2 ways, for example, as 231952900 + 210569121 = 15230^2 + 14511^2 .

It is a cyclic number.

It is not a de Polignac number, because 442522021 - 2¹³ = 442513829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 442521983 and 442522001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442522321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32800 + ... + 44281.

It is an arithmetic number, because the mean of its divisors is an integer number (110651211).

Almost surely, 2^442522021 is an apocalyptic number.

It is an amenable number.

442522021 is a deficient number, since it is larger than the sum of its proper divisors (82823).

442522021 is an equidigital number, since it uses as much as digits as its factorization.

442522021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82822.

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 442522021 is about 21036.2073815600. The cubic root of 442522021 is about 762.0409253468.

Adding to 442522021 its reverse (120225244), we get a palindrome (562747265).

The spelling of 442522021 in words is "four hundred forty-two million, five hundred twenty-two thousand, twenty-one".