163691 has 8 divisors (see below), whose sum is σ = 186624. Its totient is φ = 142120.

The previous prime is 163679. The next prime is 163697. The reversal of 163691 is 196361.

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

It is not a de Polignac number, because 163691 - 2⁶ = 163627 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 163691.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 163691.

It is not an unprimeable number, because it can be changed into a prime (163697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71 + ... + 576.

It is an arithmetic number, because the mean of its divisors is an integer number (23328).

2¹⁶³⁶⁹¹ is an apocalyptic number.

163691 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

163691 is a deficient number, since it is larger than the sum of its proper divisors (22933).

163691 is a wasteful number, since it uses less digits than its factorization.

163691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681.

The product of its digits is 972, while the sum is 26.

The square root of 163691 is about 404.5874441947. The cubic root of 163691 is about 54.7026376054.

The spelling of 163691 in words is "one hundred sixty-three thousand, six hundred ninety-one".