491566889256 has 32 divisors (see below), whose sum is σ = 1301206472640. Its totient is φ = 154217063168.

The previous prime is 491566889249. The next prime is 491566889287. The reversal of 491566889256 is 652988665194.

It is a happy number.

It is a super-2 number, since 2×491566889256² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 602409996 + ... + 602410811.

It is an arithmetic number, because the mean of its divisors is an integer number (40662702270).

Almost surely, 2^491566889256 is an apocalyptic number.

It is an amenable number.

491566889256 is an abundant number, since it is smaller than the sum of its proper divisors (809639583384).

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

491566889256 is a wasteful number, since it uses less digits than its factorization.

491566889256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1204820833 (or 1204820829 counting only the distinct ones).

The product of its digits is 223948800, while the sum is 69.

The spelling of 491566889256 in words is "four hundred ninety-one billion, five hundred sixty-six million, eight hundred eighty-nine thousand, two hundred fifty-six".