31313212231 has 8 divisors (see below), whose sum is σ = 37020546720. Its totient is φ = 25914382368.

The previous prime is 31313212213. The next prime is 31313212279. The reversal of 31313212231 is 13221231313.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31313212231 - 2⁹ = 31313211719 is a prime.

It is a super-2 number, since 2×31313212231² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31313212031) 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 7 ways as a sum of consecutive naturals, for example, 77125936 + ... + 77126341.

It is an arithmetic number, because the mean of its divisors is an integer number (4627568340).

Almost surely, 2^31313212231 is an apocalyptic number.

31313212231 is a deficient number, since it is larger than the sum of its proper divisors (5707334489).

31313212231 is a wasteful number, since it uses less digits than its factorization.

31313212231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154252313.

The product of its digits is 648, while the sum is 22.

Adding to 31313212231 its reverse (13221231313), we get a palindrome (44534443544).

The spelling of 31313212231 in words is "thirty-one billion, three hundred thirteen million, two hundred twelve thousand, two hundred thirty-one".