491171 has 2 divisors, whose sum is σ = 491172. Its totient is φ = 491170.

The previous prime is 491167. The next prime is 491201. The reversal of 491171 is 171194.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 491171 - 2² = 491167 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is equal to p₄₀₈₅₆ and since 491171 and 40856 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (491371) 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 as a sum of consecutive naturals, namely, 245585 + 245586.

It is an arithmetic number, because the mean of its divisors is an integer number (245586).

2⁴⁹¹¹⁷¹ is an apocalyptic number.

491171 is a deficient number, since it is larger than the sum of its proper divisors (1).

491171 is an equidigital number, since it uses as much as digits as its factorization.

491171 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 252, while the sum is 23.

The square root of 491171 is about 700.8359294443. The cubic root of 491171 is about 78.9001033966.

Adding to 491171 its sum of digits (23), we get a palindrome (491194).

The spelling of 491171 in words is "four hundred ninety-one thousand, one hundred seventy-one".