491779 has 4 divisors (see below), whose sum is σ = 493200. Its totient is φ = 490360.

The previous prime is 491773. The next prime is 491783. The reversal of 491779 is 977194.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 491779 - 2⁵ = 491747 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (491773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189 + ... + 1009.

It is an arithmetic number, because the mean of its divisors is an integer number (123300).

2⁴⁹¹⁷⁷⁹ is an apocalyptic number.

491779 is a deficient number, since it is larger than the sum of its proper divisors (1421).

491779 is an equidigital number, since it uses as much as digits as its factorization.

491779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1420.

The product of its digits is 15876, while the sum is 37.

The square root of 491779 is about 701.2695630070. The cubic root of 491779 is about 78.9326456834.

The spelling of 491779 in words is "four hundred ninety-one thousand, seven hundred seventy-nine".