165173257 has 4 divisors (see below), whose sum is σ = 165207316. Its totient is φ = 165139200.

The previous prime is 165173227. The next prime is 165173287. The reversal of 165173257 is 752371561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 752371561 = 23 ⋅32711807.

It is an interprime number because it is at equal distance from previous prime (165173227) and next prime (165173287).

It can be written as a sum of positive squares in 2 ways, for example, as 136913401 + 28259856 = 11701^2 + 5316^2 .

It is a cyclic number.

It is not a de Polignac number, because 165173257 - 2¹⁵ = 165140489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165173227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8244 + ... + 19957.

It is an arithmetic number, because the mean of its divisors is an integer number (41301829).

Almost surely, 2^165173257 is an apocalyptic number.

It is an amenable number.

165173257 is a deficient number, since it is larger than the sum of its proper divisors (34059).

165173257 is an equidigital number, since it uses as much as digits as its factorization.

165173257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34058.

The product of its digits is 44100, while the sum is 37.

The square root of 165173257 is about 12851.9748287958. The cubic root of 165173257 is about 548.6725640738.

The spelling of 165173257 in words is "one hundred sixty-five million, one hundred seventy-three thousand, two hundred fifty-seven".