199191 has 8 divisors (see below), whose sum is σ = 269824. Its totient is φ = 130680.

The previous prime is 199181. The next prime is 199193. The reversal of 199191 is 191991.

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

It is a de Polignac number, because none of the positive numbers 2^k-199191 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 295 + ... + 696.

It is an arithmetic number, because the mean of its divisors is an integer number (33728).

2¹⁹⁹¹⁹¹ is an apocalyptic number.

199191 is a deficient number, since it is larger than the sum of its proper divisors (70633).

199191 is an equidigital number, since it uses as much as digits as its factorization.

199191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1061.

The product of its digits is 729, while the sum is 30.

The square root of 199191 is about 446.3081894835. The cubic root of 199191 is about 58.4013971956.

It can be divided in two parts, 1991 and 91, that multiplied together give a palindrome (181181).

The spelling of 199191 in words is "one hundred ninety-nine thousand, one hundred ninety-one".