165509835241 has 9 divisors (see below), whose sum is σ = 167838267909. Its totient is φ = 163213285536.

The previous prime is 165509835173. The next prime is 165509835289. The reversal of 165509835241 is 142538905561.

The square root of 165509835241 is 406829.

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

165509835241 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 4 ways, for example, as 39271745241 + 126238090000 = 198171^2 + 355300^2 .

It is not a de Polignac number, because 165509835241 - 2¹¹ = 165509833193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165509335241) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 29695731 + ... + 29701303.

Almost surely, 2^165509835241 is an apocalyptic number.

165509835241 is the 406829-th square number.

165509835241 is the 203415-th centered octagonal number.

It is an amenable number.

165509835241 is a deficient number, since it is larger than the sum of its proper divisors (2328432668).

165509835241 is an frugal number, since it uses more digits than its factorization.

165509835241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11292 (or 5646 counting only the distinct ones).

The product of its (nonzero) digits is 1296000, while the sum is 49.

Multiplying 165509835241 by its sum of digits (49), we get a square (8109981926809 = 2847803²).

The spelling of 165509835241 in words is "one hundred sixty-five billion, five hundred nine million, eight hundred thirty-five thousand, two hundred forty-one".