165129541685 has 4 divisors (see below), whose sum is σ = 198155450028. Its totient is φ = 132103633344.

The previous prime is 165129541651. The next prime is 165129541691. The reversal of 165129541685 is 586145921561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 100120350724 + 65009190961 = 316418^2 + 254969^2 .

It is a cyclic number.

It is not a de Polignac number, because 165129541685 - 2²⁰ = 165128493109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16512954164 + ... + 16512954173.

It is an arithmetic number, because the mean of its divisors is an integer number (49538862507).

Almost surely, 2^165129541685 is an apocalyptic number.

It is an amenable number.

165129541685 is a deficient number, since it is larger than the sum of its proper divisors (33025908343).

165129541685 is an equidigital number, since it uses as much as digits as its factorization.

165129541685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33025908342.

The product of its digits is 2592000, while the sum is 53.

The spelling of 165129541685 in words is "one hundred sixty-five billion, one hundred twenty-nine million, five hundred forty-one thousand, six hundred eighty-five".