491397745824 has 192 divisors, whose sum is σ = 1491556550400. Its totient is φ = 157202648064.

The previous prime is 491397745819. The next prime is 491397745841. The reversal of 491397745824 is 428547793194.

491397745824 is a `hidden beast` number, since 4 + 91 + 3 + 9 + 77 + 458 + 24 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4125634 + ... + 4243070.

It is an arithmetic number, because the mean of its divisors is an integer number (7768523700).

Almost surely, 2^491397745824 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 491397745824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (745778275200).

491397745824 is an abundant number, since it is smaller than the sum of its proper divisors (1000158804576).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

491397745824 is a wasteful number, since it uses less digits than its factorization.

491397745824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117652 (or 117638 counting only the distinct ones).

The product of its digits is 60963840, while the sum is 63.

The spelling of 491397745824 in words is "four hundred ninety-one billion, three hundred ninety-seven million, seven hundred forty-five thousand, eight hundred twenty-four".