31023131321 has 40 divisors (see below), whose sum is σ = 40320619080. Its totient is φ = 23698676736.

The previous prime is 31023131311. The next prime is 31023131323. The reversal of 31023131321 is 12313132013.

It can be written as a sum of positive squares in 4 ways, for example, as 5880589225 + 25142542096 = 76685^2 + 158564^2 .

It is not a de Polignac number, because 31023131321 - 2⁶ = 31023131257 is a prime.

It is a super-2 number, since 2×31023131321² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31023131293 and 31023131302.

It is not an unprimeable number, because it can be changed into a prime (31023131323) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 888041 + ... + 922313.

It is an arithmetic number, because the mean of its divisors is an integer number (1008015477).

Almost surely, 2^31023131321 is an apocalyptic number.

It is an amenable number.

31023131321 is a deficient number, since it is larger than the sum of its proper divisors (9297487759).

31023131321 is an equidigital number, since it uses as much as digits as its factorization.

31023131321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34343 (or 34322 counting only the distinct ones).

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

Adding to 31023131321 its reverse (12313132013), we get a palindrome (43336263334).

The spelling of 31023131321 in words is "thirty-one billion, twenty-three million, one hundred thirty-one thousand, three hundred twenty-one".