163971 has 8 divisors (see below), whose sum is σ = 242960. Its totient is φ = 109296.

The previous prime is 163927. The next prime is 163973. The reversal of 163971 is 179361.

It is not a de Polignac number, because 163971 - 2¹⁰ = 162947 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 6073 = 163971 / (1 + 6 + 3 + 9 + 7 + 1).

It is a Duffinian number.

163971 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3010 + ... + 3063.

It is an arithmetic number, because the mean of its divisors is an integer number (30370).

2¹⁶³⁹⁷¹ is an apocalyptic number.

163971 is a deficient number, since it is larger than the sum of its proper divisors (78989).

163971 is an equidigital number, since it uses as much as digits as its factorization.

163971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6082 (or 6076 counting only the distinct ones).

The product of its digits is 1134, while the sum is 27.

The square root of 163971 is about 404.9333278455. The cubic root of 163971 is about 54.7338101877.

It can be divided in two parts, 16 and 3971, that multiplied together give a palindrome (63536).

The spelling of 163971 in words is "one hundred sixty-three thousand, nine hundred seventy-one".