31311313231 has 4 divisors (see below), whose sum is σ = 34157796264. Its totient is φ = 28464830200.

The previous prime is 31311313219. The next prime is 31311313331. The reversal of 31311313231 is 13231311313.

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 31311313231 - 2⁵ = 31311313199 is a prime.

It is a super-2 number, since 2×31311313231² (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 (31311313331) 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, 1423241500 + ... + 1423241521.

It is an arithmetic number, because the mean of its divisors is an integer number (8539449066).

Almost surely, 2^31311313231 is an apocalyptic number.

31311313231 is a deficient number, since it is larger than the sum of its proper divisors (2846483033).

31311313231 is a wasteful number, since it uses less digits than its factorization.

31311313231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2846483032.

The product of its digits is 486, while the sum is 22.

Adding to 31311313231 its reverse (13231311313), we get a palindrome (44542624544).

The spelling of 31311313231 in words is "thirty-one billion, three hundred eleven million, three hundred thirteen thousand, two hundred thirty-one".