31312211131 has 4 divisors (see below), whose sum is σ = 31431269232. Its totient is φ = 31193153032.

The previous prime is 31312211129. The next prime is 31312211153. The reversal of 31312211131 is 13111221313.

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 31312211131 - 2¹ = 31312211129 is a prime.

It is a super-2 number, since 2×31312211131² (a number of 22 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 = 31312211099 and 31312211108.

It is not an unprimeable number, because it can be changed into a prime (31312221131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59528656 + ... + 59529181.

It is an arithmetic number, because the mean of its divisors is an integer number (7857817308).

Almost surely, 2^31312211131 is an apocalyptic number.

31312211131 is a deficient number, since it is larger than the sum of its proper divisors (119058101).

31312211131 is a wasteful number, since it uses less digits than its factorization.

31312211131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119058100.

The product of its digits is 108, while the sum is 19.

Adding to 31312211131 its reverse (13111221313), we get a palindrome (44423432444).

The spelling of 31312211131 in words is "thirty-one billion, three hundred twelve million, two hundred eleven thousand, one hundred thirty-one".