31311012321 has 32 divisors (see below), whose sum is σ = 47233643520. Its totient is φ = 20495452032.

The previous prime is 31311012287. The next prime is 31311012329. The reversal of 31311012321 is 12321011313.

31311012321 is a `hidden beast` number, since 31 + 311 + 0 + 1 + 2 + 321 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-31311012321 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31311012294 and 31311012303.

It is not an unprimeable number, because it can be changed into a prime (31311012329) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 403915 + ... + 475151.

It is an arithmetic number, because the mean of its divisors is an integer number (1476051360).

Almost surely, 2^31311012321 is an apocalyptic number.

It is an amenable number.

31311012321 is a deficient number, since it is larger than the sum of its proper divisors (15922631199).

31311012321 is a wasteful number, since it uses less digits than its factorization.

31311012321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71542 (or 71536 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 31311012321 its reverse (12321011313), we get a palindrome (43632023634).

The spelling of 31311012321 in words is "thirty-one billion, three hundred eleven million, twelve thousand, three hundred twenty-one".