191957 has 4 divisors (see below), whose sum is σ = 202080. Its totient is φ = 181836.

The previous prime is 191953. The next prime is 191969. The reversal of 191957 is 759191.

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 a cyclic number.

It is not a de Polignac number, because 191957 - 2² = 191953 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 191957.

It is not an unprimeable number, because it can be changed into a prime (191953) 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, 5033 + ... + 5070.

It is an arithmetic number, because the mean of its divisors is an integer number (50520).

2¹⁹¹⁹⁵⁷ is an apocalyptic number.

It is an amenable number.

191957 is a deficient number, since it is larger than the sum of its proper divisors (10123).

191957 is a wasteful number, since it uses less digits than its factorization.

191957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10122.

The product of its digits is 2835, while the sum is 32.

The square root of 191957 is about 438.1289764442. The cubic root of 191957 is about 57.6856757733.

The spelling of 191957 in words is "one hundred ninety-one thousand, nine hundred fifty-seven".