321402321 has 24 divisors (see below), whose sum is σ = 478140936. Its totient is φ = 207912960.

The previous prime is 321402317. The next prime is 321402353. The reversal of 321402321 is 123204123.

It can be written as a sum of positive squares in 4 ways, for example, as 50339025 + 271063296 = 7095^2 + 16464^2 .

It is not a de Polignac number, because 321402321 - 2² = 321402317 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 321402294 and 321402303.

It is not an unprimeable number, because it can be changed into a prime (321402421) 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 23 ways as a sum of consecutive naturals, for example, 68961 + ... + 73473.

It is an arithmetic number, because the mean of its divisors is an integer number (19922539).

Almost surely, 2^321402321 is an apocalyptic number.

It is an amenable number.

321402321 is a deficient number, since it is larger than the sum of its proper divisors (156738615).

321402321 is a wasteful number, since it uses less digits than its factorization.

321402321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4753 (or 4750 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 321402321 is about 17927.6970355927. The cubic root of 321402321 is about 684.9880623774.

Adding to 321402321 its reverse (123204123), we get a palindrome (444606444).

The spelling of 321402321 in words is "three hundred twenty-one million, four hundred two thousand, three hundred twenty-one".