491889771 has 12 divisors (see below), whose sum is σ = 727031448. Its totient is φ = 320300064.

The previous prime is 491889731. The next prime is 491889773. The reversal of 491889771 is 177988194.

491889771 is a `hidden beast` number, since 491 + 8 + 89 + 7 + 71 = 666.

It is not a de Polignac number, because 491889771 - 2¹¹ = 491887723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (491889773) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 635130 + ... + 635903.

It is an arithmetic number, because the mean of its divisors is an integer number (60585954).

Almost surely, 2^491889771 is an apocalyptic number.

491889771 is a deficient number, since it is larger than the sum of its proper divisors (235141677).

491889771 is a wasteful number, since it uses less digits than its factorization.

491889771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1271082 (or 1271079 counting only the distinct ones).

The product of its digits is 1016064, while the sum is 54.

The square root of 491889771 is about 22178.5881200765. The cubic root of 491889771 is about 789.3857164588.

The spelling of 491889771 in words is "four hundred ninety-one million, eight hundred eighty-nine thousand, seven hundred seventy-one".