191397 has 4 divisors (see below), whose sum is σ = 255200. Its totient is φ = 127596.

The previous prime is 191353. The next prime is 191413. The reversal of 191397 is 793191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 191397 - 2⁸ = 191141 is a prime.

It is a D-number.

It is a Duffinian number.

191397 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191297) 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 3 ways as a sum of consecutive naturals, for example, 31897 + ... + 31902.

It is an arithmetic number, because the mean of its divisors is an integer number (63800).

2¹⁹¹³⁹⁷ is an apocalyptic number.

It is an amenable number.

191397 is a deficient number, since it is larger than the sum of its proper divisors (63803).

191397 is an equidigital number, since it uses as much as digits as its factorization.

191397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63802.

The product of its digits is 1701, while the sum is 30.

The square root of 191397 is about 437.4894284437. The cubic root of 191397 is about 57.6295252758.

The spelling of 191397 in words is "one hundred ninety-one thousand, three hundred ninety-seven".