31111213131 has 10 divisors (see below), whose sum is σ = 46474775292. Its totient is φ = 20740808700.

The previous prime is 31111213117. The next prime is 31111213153. The reversal of 31111213131 is 13131211113.

31111213131 is a `hidden beast` number, since 311 + 11 + 213 + 131 = 666.

It is not a de Polignac number, because 31111213131 - 2⁵ = 31111213099 is a prime.

It is a super-2 number, since 2×31111213131² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31111213181) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 192044445 + ... + 192044606.

Almost surely, 2^31111213131 is an apocalyptic number.

31111213131 is a deficient number, since it is larger than the sum of its proper divisors (15363562161).

31111213131 is an equidigital number, since it uses as much as digits as its factorization.

31111213131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384089063 (or 384089054 counting only the distinct ones).

The product of its digits is 54, while the sum is 18.

Adding to 31111213131 its reverse (13131211113), we get a palindrome (44242424244).

The spelling of 31111213131 in words is "thirty-one billion, one hundred eleven million, two hundred thirteen thousand, one hundred thirty-one".