321442021 has 4 divisors (see below), whose sum is σ = 323599500. Its totient is φ = 319284544.

The previous prime is 321441949. The next prime is 321442027. The reversal of 321442021 is 120244123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120244123 = 317 ⋅379319.

It can be written as a sum of positive squares in 2 ways, for example, as 11189025 + 310252996 = 3345^2 + 17614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321442021 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 321442021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321442027) 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, 1078516 + ... + 1078813.

It is an arithmetic number, because the mean of its divisors is an integer number (80899875).

Almost surely, 2^321442021 is an apocalyptic number.

It is an amenable number.

321442021 is a deficient number, since it is larger than the sum of its proper divisors (2157479).

321442021 is a wasteful number, since it uses less digits than its factorization.

321442021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2157478.

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

The square root of 321442021 is about 17928.8042267185. The cubic root of 321442021 is about 685.0162647318.

Adding to 321442021 its reverse (120244123), we get a palindrome (441686144).

The spelling of 321442021 in words is "three hundred twenty-one million, four hundred forty-two thousand, twenty-one".