81329325328 has 10 divisors (see below), whose sum is σ = 157575567854. Its totient is φ = 40664662656.

The previous prime is 81329325317. The next prime is 81329325373. The reversal of 81329325328 is 82352392318.

It can be written as a sum of positive squares in only one way, i.e., 76935226384 + 4394098944 = 277372^2 + 66288^2 .

It is a super-2 number, since 2×81329325328² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 2541541401 + ... + 2541541432.

Almost surely, 2^81329325328 is an apocalyptic number.

It is an amenable number.

81329325328 is a deficient number, since it is larger than the sum of its proper divisors (76246242526).

81329325328 is a wasteful number, since it uses less digits than its factorization.

81329325328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5083082841 (or 5083082835 counting only the distinct ones).

The product of its digits is 622080, while the sum is 46.

The spelling of 81329325328 in words is "eighty-one billion, three hundred twenty-nine million, three hundred twenty-five thousand, three hundred twenty-eight".