81771755758516 has 24 divisors (see below), whose sum is σ = 143339492249856. Its totient is φ = 40817618096640.

The previous prime is 81771755758507. The next prime is 81771755758541. The reversal of 81771755758516 is 61585755717718.

81771755758516 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (73) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117096660 + ... + 117792916.

It is an arithmetic number, because the mean of its divisors is an integer number (5972478843744).

Almost surely, 2^{81771755758516} is an apocalyptic number.

It is an amenable number.

81771755758516 is a deficient number, since it is larger than the sum of its proper divisors (61567736491340).

81771755758516 is a wasteful number, since it uses less digits than its factorization.

81771755758516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 745239 (or 745237 counting only the distinct ones).

The product of its digits is 576240000, while the sum is 73.

The spelling of 81771755758516 in words is "eighty-one trillion, seven hundred seventy-one billion, seven hundred fifty-five million, seven hundred fifty-eight thousand, five hundred sixteen".