31213313331331 has 4 divisors (see below), whose sum is σ = 31313036377432. Its totient is φ = 31113590285232.

The previous prime is 31213313331301. The next prime is 31213313331367. The reversal of 31213313331331 is 13313331331213.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31213313331331 - 2⁹ = 31213313330819 is a prime.

It is a super-2 number, since 2×31213313331331² (a number of 28 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 = 31213313331293 and 31213313331302.

It is not an unprimeable number, because it can be changed into a prime (31213313331301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49861522581 + ... + 49861523206.

It is an arithmetic number, because the mean of its divisors is an integer number (7828259094358).

Almost surely, 2^{31213313331331} is an apocalyptic number.

31213313331331 is a deficient number, since it is larger than the sum of its proper divisors (99723046101).

31213313331331 is an equidigital number, since it uses as much as digits as its factorization.

31213313331331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99723046100.

The product of its digits is 13122, while the sum is 31.

Adding to 31213313331331 its reverse (13313331331213), we get a palindrome (44526644662544).

The spelling of 31213313331331 in words is "thirty-one trillion, two hundred thirteen billion, three hundred thirteen million, three hundred thirty-one thousand, three hundred thirty-one".