81597065104 has 15 divisors (see below), whose sum is σ = 158096527473. Its totient is φ = 40797961248.

The previous prime is 81597065089. The next prime is 81597065113. The reversal of 81597065104 is 40156079518.

The square root of 81597065104 is 285652.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 40973856400 + 40623208704 = 202420^2 + 201552^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1106902 + ... + 1178314.

Almost surely, 2^81597065104 is an apocalyptic number.

81597065104 is the 285652-nd square number.

It is an amenable number.

81597065104 is a deficient number, since it is larger than the sum of its proper divisors (76499462369).

81597065104 is an frugal number, since it uses more digits than its factorization.

81597065104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142834 (or 71415 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 46.

The spelling of 81597065104 in words is "eighty-one billion, five hundred ninety-seven million, sixty-five thousand, one hundred four".