13165497081 has 135 divisors (see below), whose sum is σ = 23195211039. Its totient is φ = 7435216800.

The previous prime is 13165497049. The next prime is 13165497133. The reversal of 13165497081 is 18079456131.

13165497081 = 7255² + 7256² + ... + 7496².

The square root of 13165497081 is 114741.

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

13165497081 is a `hidden beast` number, since 1 + 31 + 6 + 549 + 70 + 8 + 1 = 666.

13165497081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 428117481 + 12737379600 = 20691^2 + 112860^2 .

It is not a de Polignac number, because 13165497081 - 2⁵ = 13165497049 is a prime.

It is a super-2 number, since 2×13165497081² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13165497011) 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 134 ways as a sum of consecutive naturals, for example, 215827791 + ... + 215827851.

Almost surely, 2^13165497081 is an apocalyptic number.

13165497081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

13165497081 is the 114741-st square number.

13165497081 is the 57371-st centered octagonal number.

It is an amenable number.

13165497081 is a deficient number, since it is larger than the sum of its proper divisors (10029713958).

13165497081 is an equidigital number, since it uses as much as digits as its factorization.

13165497081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194 (or 94 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The spelling of 13165497081 in words is "thirteen billion, one hundred sixty-five million, four hundred ninety-seven thousand, eighty-one".