31323011321 has 6 divisors (see below), whose sum is σ = 36436972410. Its totient is φ = 26848295376.

The previous prime is 31323011299. The next prime is 31323011341. The reversal of 31323011321 is 12311032313.

It can be written as a sum of positive squares in only one way, i.e., 19132422400 + 12190588921 = 138320^2 + 110411^2 .

It is not a de Polignac number, because 31323011321 - 2²² = 31318817017 is a prime.

It is a super-2 number, since 2×31323011321² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31323011293 and 31323011302.

It is not an unprimeable number, because it can be changed into a prime (31323011341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 319622516 + ... + 319622613.

It is an arithmetic number, because the mean of its divisors is an integer number (6072828735).

Almost surely, 2^31323011321 is an apocalyptic number.

It is an amenable number.

31323011321 is a deficient number, since it is larger than the sum of its proper divisors (5113961089).

31323011321 is an equidigital number, since it uses as much as digits as its factorization.

31323011321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639245143 (or 639245136 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 31323011321 its reverse (12311032313), we get a palindrome (43634043634).

The spelling of 31323011321 in words is "thirty-one billion, three hundred twenty-three million, eleven thousand, three hundred twenty-one".