81307843033 has 2 divisors, whose sum is σ = 81307843034. Its totient is φ = 81307843032.

The previous prime is 81307843013. The next prime is 81307843063. The reversal of 81307843033 is 33034870318.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54890866944 + 26416976089 = 234288^2 + 162533^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81307843033 is a prime.

It is a super-2 number, since 2×81307843033² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81307843013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40653921516 + 40653921517.

It is an arithmetic number, because the mean of its divisors is an integer number (40653921517).

Almost surely, 2^81307843033 is an apocalyptic number.

It is an amenable number.

81307843033 is a deficient number, since it is larger than the sum of its proper divisors (1).

81307843033 is an equidigital number, since it uses as much as digits as its factorization.

81307843033 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 40.

The spelling of 81307843033 in words is "eighty-one billion, three hundred seven million, eight hundred forty-three thousand, thirty-three".