165165817 has 8 divisors (see below), whose sum is σ = 175480200. Its totient is φ = 155159424.

The previous prime is 165165797. The next prime is 165165823. The reversal of 165165817 is 718561561.

It can be written as a sum of positive squares in 4 ways, for example, as 26020201 + 139145616 = 5101^2 + 11796^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165165817 - 2¹¹ = 165163769 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 165165817.

It is not an unprimeable number, because it can be changed into a prime (165165887) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75892 + ... + 78037.

It is an arithmetic number, because the mean of its divisors is an integer number (21935025).

Almost surely, 2^165165817 is an apocalyptic number.

It is an amenable number.

165165817 is a deficient number, since it is larger than the sum of its proper divisors (10314383).

165165817 is a wasteful number, since it uses less digits than its factorization.

165165817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153995.

The product of its digits is 50400, while the sum is 40.

The square root of 165165817 is about 12851.6853758564. The cubic root of 165165817 is about 548.6643258855.

The spelling of 165165817 in words is "one hundred sixty-five million, one hundred sixty-five thousand, eight hundred seventeen".