81888799788767 has 2 divisors, whose sum is σ = 81888799788768. Its totient is φ = 81888799788766.

The previous prime is 81888799788749. The next prime is 81888799788863. The reversal of 81888799788767 is 76788799788818.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81888799788767 - 2⁶ = 81888799788703 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81888799788067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40944399894383 + 40944399894384.

It is an arithmetic number, because the mean of its divisors is an integer number (40944399894384).

Almost surely, 2^{81888799788767} is an apocalyptic number.

81888799788767 is a deficient number, since it is larger than the sum of its proper divisors (1).

81888799788767 is an equidigital number, since it uses as much as digits as its factorization.

81888799788767 is an evil number, because the sum of its binary digits is even.

The product of its digits is 305892163584, while the sum is 101.

The spelling of 81888799788767 in words is "eighty-one trillion, eight hundred eighty-eight billion, seven hundred ninety-nine million, seven hundred eighty-eight thousand, seven hundred sixty-seven".