81718350052549 has 16 divisors (see below), whose sum is σ = 98886766118400. Its totient is φ = 65923583457024.

The previous prime is 81718350052511. The next prime is 81718350052571. The reversal of 81718350052549 is 94525005381718.

It is a cyclic number.

It is not a de Polignac number, because 81718350052549 - 2⁷ = 81718350052421 is a prime.

It is a super-2 number, since 2×81718350052549² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81718350052493 and 81718350052502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81718350052049) 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 in 15 ways as a sum of consecutive naturals, for example, 15108547 + ... + 19791535.

It is an arithmetic number, because the mean of its divisors is an integer number (6180422882400).

Almost surely, 2^{81718350052549} is an apocalyptic number.

It is an amenable number.

81718350052549 is a deficient number, since it is larger than the sum of its proper divisors (17168416065851).

81718350052549 is a wasteful number, since it uses less digits than its factorization.

81718350052549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4829652.

The product of its (nonzero) digits is 12096000, while the sum is 58.

The spelling of 81718350052549 in words is "eighty-one trillion, seven hundred eighteen billion, three hundred fifty million, fifty-two thousand, five hundred forty-nine".