13021320331 has 4 divisors (see below), whose sum is σ = 13706653000. Its totient is φ = 12335987664.

The previous prime is 13021320283. The next prime is 13021320337. The reversal of 13021320331 is 13302312031.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13302312031 = 17 ⋅782488943.

It is a cyclic number.

It is not a de Polignac number, because 13021320331 - 2⁷ = 13021320203 is a prime.

It is a super-2 number, since 2×13021320331² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 685332649 = 13021320331 / (1 + 3 + 0 + 2 + 1 + 3 + 2 + 0 + 3 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13021320299 and 13021320308.

It is not an unprimeable number, because it can be changed into a prime (13021320337) 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, 342666306 + ... + 342666343.

It is an arithmetic number, because the mean of its divisors is an integer number (3426663250).

Almost surely, 2^13021320331 is an apocalyptic number.

13021320331 is a deficient number, since it is larger than the sum of its proper divisors (685332669).

13021320331 is an equidigital number, since it uses as much as digits as its factorization.

13021320331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685332668.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 13021320331 its reverse (13302312031), we get a palindrome (26323632362).

It can be divided in two parts, 130213 and 20331, that added together give a square (150544 = 388²).

The spelling of 13021320331 in words is "thirteen billion, twenty-one million, three hundred twenty thousand, three hundred thirty-one".