442244021 has 4 divisors (see below), whose sum is σ = 442328844. Its totient is φ = 442159200.

The previous prime is 442243987. The next prime is 442244027. The reversal of 442244021 is 120442244.

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 305026225 + 137217796 = 17465^2 + 11714^2 .

It is a cyclic number.

It is not a de Polignac number, because 442244021 - 2⁶ = 442243957 is a prime.

It is a super-2 number, since 2×442244021² = 391159548220496882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442244027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34040 + ... + 45201.

It is an arithmetic number, because the mean of its divisors is an integer number (110582211).

Almost surely, 2^442244021 is an apocalyptic number.

It is an amenable number.

442244021 is a deficient number, since it is larger than the sum of its proper divisors (84823).

442244021 is an equidigital number, since it uses as much as digits as its factorization.

442244021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84822.

The product of its (nonzero) digits is 2048, while the sum is 23.

The square root of 442244021 is about 21029.5986885152. The cubic root of 442244021 is about 761.8813161486.

Adding to 442244021 its reverse (120442244), we get a palindrome (562686265).

The spelling of 442244021 in words is "four hundred forty-two million, two hundred forty-four thousand, twenty-one".