491263751 has 12 divisors (see below), whose sum is σ = 540520512. Its totient is φ = 446160000.

The previous prime is 491263723. The next prime is 491263757. The reversal of 491263751 is 157362194.

It is not a de Polignac number, because 491263751 - 2²² = 487069447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491263757) 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 11 ways as a sum of consecutive naturals, for example, 235031 + ... + 237111.

It is an arithmetic number, because the mean of its divisors is an integer number (45043376).

Almost surely, 2^491263751 is an apocalyptic number.

491263751 is a deficient number, since it is larger than the sum of its proper divisors (49256761).

491263751 is a wasteful number, since it uses less digits than its factorization.

491263751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4054 (or 4043 counting only the distinct ones).

The product of its digits is 45360, while the sum is 38.

The square root of 491263751 is about 22164.4704651386. The cubic root of 491263751 is about 789.0506948985.

The spelling of 491263751 in words is "four hundred ninety-one million, two hundred sixty-three thousand, seven hundred fifty-one".