195191 has 4 divisors (see below), whose sum is σ = 199392. Its totient is φ = 190992.

The previous prime is 195163. The next prime is 195193. The reversal of 195191 is 191591.

195191 = 40² + 41² + ... + 86².

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 191591 = 283 ⋅677.

It is a cyclic number.

It is not a de Polignac number, because 195191 - 2⁶ = 195127 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 195191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195193) 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 3 ways as a sum of consecutive naturals, for example, 2030 + ... + 2123.

It is an arithmetic number, because the mean of its divisors is an integer number (49848).

2¹⁹⁵¹⁹¹ is an apocalyptic number.

195191 is a deficient number, since it is larger than the sum of its proper divisors (4201).

195191 is an equidigital number, since it uses as much as digits as its factorization.

195191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4200.

The product of its digits is 405, while the sum is 26.

The square root of 195191 is about 441.8042552987. The cubic root of 195191 is about 58.0078269263.

Subtracting from 195191 its reverse (191591), we obtain a square (3600 = 60²).

The spelling of 195191 in words is "one hundred ninety-five thousand, one hundred ninety-one".