442122221 has 4 divisors (see below), whose sum is σ = 442494012. Its totient is φ = 441750432.

The previous prime is 442122209. The next prime is 442122251. The reversal of 442122221 is 122221244.

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 289476196 + 152646025 = 17014^2 + 12355^2 .

It is a cyclic number.

It is not a de Polignac number, because 442122221 - 2¹⁴ = 442105837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 442122193 and 442122202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442122251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 184106 + ... + 186491.

It is an arithmetic number, because the mean of its divisors is an integer number (110623503).

Almost surely, 2^442122221 is an apocalyptic number.

It is an amenable number.

442122221 is a deficient number, since it is larger than the sum of its proper divisors (371791).

442122221 is a wasteful number, since it uses less digits than its factorization.

442122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371790.

The product of its digits is 512, while the sum is 20.

The square root of 442122221 is about 21026.7025707789. The cubic root of 442122221 is about 761.8113655780.

Adding to 442122221 its reverse (122221244), we get a palindrome (564343465).

The spelling of 442122221 in words is "four hundred forty-two million, one hundred twenty-two thousand, two hundred twenty-one".