191023 has 8 divisors (see below), whose sum is σ = 226080. Its totient is φ = 157920.

The previous prime is 191021. The next prime is 191027. The reversal of 191023 is 320191.

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

It is not a de Polignac number, because 191023 - 2¹ = 191021 is a prime.

It is a Duffinian number.

191023 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 190988 and 191006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191021) 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 7 ways as a sum of consecutive naturals, for example, 268 + ... + 673.

It is an arithmetic number, because the mean of its divisors is an integer number (28260).

2¹⁹¹⁰²³ is an apocalyptic number.

191023 is a deficient number, since it is larger than the sum of its proper divisors (35057).

191023 is an equidigital number, since it uses as much as digits as its factorization.

191023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 977.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 191023 is about 437.0617805299. The cubic root of 191023 is about 57.5919637387.

Subtracting from 191023 its product of nonzero digits (54), we obtain a square (190969 = 437²).

The spelling of 191023 in words is "one hundred ninety-one thousand, twenty-three".