191623 has 4 divisors (see below), whose sum is σ = 196840. Its totient is φ = 186408.

The previous prime is 191621. The next prime is 191627. The reversal of 191623 is 326191.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 326191 = 79 ⋅4129.

It is a cyclic number.

It is not a de Polignac number, because 191623 - 2¹ = 191621 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 191594 and 191603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2553 + ... + 2626.

It is an arithmetic number, because the mean of its divisors is an integer number (49210).

2¹⁹¹⁶²³ is an apocalyptic number.

191623 is a deficient number, since it is larger than the sum of its proper divisors (5217).

191623 is an equidigital number, since it uses as much as digits as its factorization.

191623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5216.

The product of its digits is 324, while the sum is 22.

The square root of 191623 is about 437.7476441970. The cubic root of 191623 is about 57.6521991766.

The spelling of 191623 in words is "one hundred ninety-one thousand, six hundred twenty-three".