491481389256 has 64 divisors (see below), whose sum is σ = 1443511782720. Its totient is φ = 137477310720.

The previous prime is 491481389251. The next prime is 491481389257. The reversal of 491481389256 is 652983184194.

It is a self number, because there is not a number n which added to its sum of digits gives 491481389256.

It is not an unprimeable number, because it can be changed into a prime (491481389251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71599335 + ... + 71606198.

It is an arithmetic number, because the mean of its divisors is an integer number (22554871605).

Almost surely, 2^491481389256 is an apocalyptic number.

It is an amenable number.

491481389256 is an abundant number, since it is smaller than the sum of its proper divisors (952030393464).

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

491481389256 is a wasteful number, since it uses less digits than its factorization.

491481389256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143205566 (or 143205562 counting only the distinct ones).

The product of its digits is 14929920, while the sum is 60.

The spelling of 491481389256 in words is "four hundred ninety-one billion, four hundred eighty-one million, three hundred eighty-nine thousand, two hundred fifty-six".