193891 has 2 divisors, whose sum is σ = 193892. Its totient is φ = 193890.

The previous prime is 193883. The next prime is 193937. The reversal of 193891 is 198391.

It is a weak prime.

It is an emirp because it is prime and its reverse (198391) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 193891 - 2³ = 193883 is a prime.

It is not a weakly prime, because it can be changed into another prime (193811) 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 as a sum of consecutive naturals, namely, 96945 + 96946.

It is an arithmetic number, because the mean of its divisors is an integer number (96946).

2¹⁹³⁸⁹¹ is an apocalyptic number.

193891 is a deficient number, since it is larger than the sum of its proper divisors (1).

193891 is an equidigital number, since it uses as much as digits as its factorization.

193891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1944, while the sum is 31.

The square root of 193891 is about 440.3305576496. The cubic root of 193891 is about 57.8787598221.

The spelling of 193891 in words is "one hundred ninety-three thousand, eight hundred ninety-one".