81347518089 has 6 divisors (see below), whose sum is σ = 117501970586. Its totient is φ = 54231678720.

The previous prime is 81347518051. The next prime is 81347518117. The reversal of 81347518089 is 98081574318.

81347518089 is a `hidden beast` number, since 8 + 1 + 3 + 47 + 518 + 0 + 89 = 666.

It can be written as a sum of positive squares in only one way, i.e., 50846642064 + 30500876025 = 225492^2 + 174645^2 .

It is not a de Polignac number, because 81347518089 - 2²³ = 81339129481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81347518019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4519306552 + ... + 4519306569.

Almost surely, 2^81347518089 is an apocalyptic number.

It is an amenable number.

81347518089 is a deficient number, since it is larger than the sum of its proper divisors (36154452497).

81347518089 is a wasteful number, since it uses less digits than its factorization.

81347518089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9038613127 (or 9038613124 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 54.

The spelling of 81347518089 in words is "eighty-one billion, three hundred forty-seven million, five hundred eighteen thousand, eighty-nine".