81328618273 has 8 divisors (see below), whose sum is σ = 98414462592. Its totient is φ = 65609641536.

The previous prime is 81328618249. The next prime is 81328618291. The reversal of 81328618273 is 37281682318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81328618273 - 2²⁵ = 81295063841 is a prime.

It is a super-2 number, since 2×81328618273² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81320618273) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 341716765 + ... + 341717002.

It is an arithmetic number, because the mean of its divisors is an integer number (12301807824).

Almost surely, 2^81328618273 is an apocalyptic number.

It is an amenable number.

81328618273 is a deficient number, since it is larger than the sum of its proper divisors (17085844319).

81328618273 is a wasteful number, since it uses less digits than its factorization.

81328618273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 683433791.

The product of its digits is 774144, while the sum is 49.

The spelling of 81328618273 in words is "eighty-one billion, three hundred twenty-eight million, six hundred eighteen thousand, two hundred seventy-three".