165036965509 has 16 divisors (see below), whose sum is σ = 180566694000. Its totient is φ = 149930942976.

The previous prime is 165036965473. The next prime is 165036965521. The reversal of 165036965509 is 905569630561.

It can be written as a sum of positive squares in 8 ways, for example, as 355209409 + 164681756100 = 18847^2 + 405810^2 .

It is a cyclic number.

It is not a de Polignac number, because 165036965509 - 2⁹ = 165036964997 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 165036965509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165036965309) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 179704 + ... + 601969.

It is an arithmetic number, because the mean of its divisors is an integer number (11285418375).

Almost surely, 2^165036965509 is an apocalyptic number.

It is an amenable number.

165036965509 is a deficient number, since it is larger than the sum of its proper divisors (15529728491).

165036965509 is a wasteful number, since it uses less digits than its factorization.

165036965509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781944.

The product of its (nonzero) digits is 6561000, while the sum is 55.

It can be divided in two parts, 1650369 and 65509, that added together give a triangular number (1715878 = T₁₈₅₂).

The spelling of 165036965509 in words is "one hundred sixty-five billion, thirty-six million, nine hundred sixty-five thousand, five hundred nine".