165997 has 6 divisors (see below), whose sum is σ = 180362. Its totient is φ = 151872.

The previous prime is 165983. The next prime is 166013. The reversal of 165997 is 799561.

It can be written as a sum of positive squares in 3 ways, for example, as 32041 + 133956 = 179^2 + 366^2 .

It is a de Polignac number, because none of the positive numbers 2^k-165997 is a prime.

Its product of digits (17010) is a multiple of the sum of its prime divisors (126).

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165947) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1413 + ... + 1525.

2¹⁶⁵⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

165997 is a deficient number, since it is larger than the sum of its proper divisors (14365).

165997 is an equidigital number, since it uses as much as digits as its factorization.

165997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239 (or 126 counting only the distinct ones).

The product of its digits is 17010, while the sum is 37.

The square root of 165997 is about 407.4272941274. The cubic root of 165997 is about 54.9583155228.

The spelling of 165997 in words is "one hundred sixty-five thousand, nine hundred ninety-seven".