31031131231 has 2 divisors, whose sum is σ = 31031131232. Its totient is φ = 31031131230.

The previous prime is 31031131217. The next prime is 31031131297. The reversal of 31031131231 is 13213113013.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31031131231 - 2⁵ = 31031131199 is a prime.

It is a super-2 number, since 2×31031131231² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31031131199 and 31031131208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31031131211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15515565615 + 15515565616.

It is an arithmetic number, because the mean of its divisors is an integer number (15515565616).

Almost surely, 2^31031131231 is an apocalyptic number.

31031131231 is a deficient number, since it is larger than the sum of its proper divisors (1).

31031131231 is an equidigital number, since it uses as much as digits as its factorization.

31031131231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 19.

Adding to 31031131231 its reverse (13213113013), we get a palindrome (44244244244).

The spelling of 31031131231 in words is "thirty-one billion, thirty-one million, one hundred thirty-one thousand, two hundred thirty-one".