165971 has 8 divisors (see below), whose sum is σ = 189504. Its totient is φ = 144000.

The previous prime is 165961. The next prime is 165983. The reversal of 165971 is 179561.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155 + ... + 596.

It is an arithmetic number, because the mean of its divisors is an integer number (23688).

2¹⁶⁵⁹⁷¹ is an apocalyptic number.

165971 is a deficient number, since it is larger than the sum of its proper divisors (23533).

165971 is a wasteful number, since it uses less digits than its factorization.

165971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 781.

The product of its digits is 1890, while the sum is 29.

The square root of 165971 is about 407.3953853445. The cubic root of 165971 is about 54.9554460114.

The spelling of 165971 in words is "one hundred sixty-five thousand, nine hundred seventy-one".