81031037831 has 2 divisors, whose sum is σ = 81031037832. Its totient is φ = 81031037830.

The previous prime is 81031037821. The next prime is 81031037849. The reversal of 81031037831 is 13873013018.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81031037831 - 2⁶ = 81031037767 is a prime.

It is a super-2 number, since 2×81031037831² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81031037791 and 81031037800.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81031037821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40515518915 + 40515518916.

It is an arithmetic number, because the mean of its divisors is an integer number (40515518916).

Almost surely, 2^81031037831 is an apocalyptic number.

81031037831 is a deficient number, since it is larger than the sum of its proper divisors (1).

81031037831 is an equidigital number, since it uses as much as digits as its factorization.

81031037831 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 35.

The spelling of 81031037831 in words is "eighty-one billion, thirty-one million, thirty-seven thousand, eight hundred thirty-one".