321320402503 has 4 divisors (see below), whose sum is σ = 326766511080. Its totient is φ = 315874293928.

The previous prime is 321320402479. The next prime is 321320402531. The reversal of 321320402503 is 305204023123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 305204023123 = 71 ⋅4298648213.

It is a de Polignac number, because none of the positive numbers 2^k-321320402503 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321320402593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2723054200 + ... + 2723054317.

It is an arithmetic number, because the mean of its divisors is an integer number (81691627770).

Almost surely, 2^321320402503 is an apocalyptic number.

321320402503 is a deficient number, since it is larger than the sum of its proper divisors (5446108577).

321320402503 is an equidigital number, since it uses as much as digits as its factorization.

321320402503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5446108576.

The product of its (nonzero) digits is 4320, while the sum is 25.

Adding to 321320402503 its reverse (305204023123), we get a palindrome (626524425626).

The spelling of 321320402503 in words is "three hundred twenty-one billion, three hundred twenty million, four hundred two thousand, five hundred three".