491276391 has 16 divisors (see below), whose sum is σ = 672050400. Its totient is φ = 319034880.

The previous prime is 491276381. The next prime is 491276449. The reversal of 491276391 is 193672194.

It is not a de Polignac number, because 491276391 - 2²⁵ = 457721959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491276341) 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 in 15 ways as a sum of consecutive naturals, for example, 87435 + ... + 92883.

It is an arithmetic number, because the mean of its divisors is an integer number (42003150).

Almost surely, 2^491276391 is an apocalyptic number.

491276391 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

491276391 is a deficient number, since it is larger than the sum of its proper divisors (180774009).

491276391 is a wasteful number, since it uses less digits than its factorization.

491276391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6226.

The product of its digits is 81648, while the sum is 42.

The square root of 491276391 is about 22164.7556043373. The cubic root of 491276391 is about 789.0574621495.

The spelling of 491276391 in words is "four hundred ninety-one million, two hundred seventy-six thousand, three hundred ninety-one".