81754766831 has 2 divisors, whose sum is σ = 81754766832. Its totient is φ = 81754766830.

The previous prime is 81754766813. The next prime is 81754766879. The reversal of 81754766831 is 13866745718.

Together with previous prime (81754766813) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81754766831 is a prime.

It is a super-2 number, since 2×81754766831² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81754766131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40877383415 + 40877383416.

It is an arithmetic number, because the mean of its divisors is an integer number (40877383416).

Almost surely, 2^81754766831 is an apocalyptic number.

81754766831 is a deficient number, since it is larger than the sum of its proper divisors (1).

81754766831 is an equidigital number, since it uses as much as digits as its factorization.

81754766831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6773760, while the sum is 56.

The spelling of 81754766831 in words is "eighty-one billion, seven hundred fifty-four million, seven hundred sixty-six thousand, eight hundred thirty-one".