163491 has 4 divisors (see below), whose sum is σ = 217992. Its totient is φ = 108992.

The previous prime is 163487. The next prime is 163517. The reversal of 163491 is 194361.

163491 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 163491 - 2² = 163487 is a prime.

It is a D-number.

163491 is strictly pandigital in base 7.

It is not an unprimeable number, because it can be changed into a prime (163411) 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, 27246 + ... + 27251.

It is an arithmetic number, because the mean of its divisors is an integer number (54498).

2¹⁶³⁴⁹¹ is an apocalyptic number.

163491 is a deficient number, since it is larger than the sum of its proper divisors (54501).

163491 is an equidigital number, since it uses as much as digits as its factorization.

163491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54500.

The product of its digits is 648, while the sum is 24.

The square root of 163491 is about 404.3402032942. The cubic root of 163491 is about 54.6803497046.

The spelling of 163491 in words is "one hundred sixty-three thousand, four hundred ninety-one".