491451564 has 12 divisors (see below), whose sum is σ = 1146720344. Its totient is φ = 163817184.

The previous prime is 491451553. The next prime is 491451593. The reversal of 491451564 is 465154194.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20477137 + ... + 20477160.

Almost surely, 2^491451564 is an apocalyptic number.

It is an amenable number.

491451564 is an abundant number, since it is smaller than the sum of its proper divisors (655268780).

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

491451564 is a wasteful number, since it uses less digits than its factorization.

491451564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40954304 (or 40954302 counting only the distinct ones).

The product of its digits is 86400, while the sum is 39.

The square root of 491451564 is about 22168.7068635047. The cubic root of 491451564 is about 789.1512349830.

The spelling of 491451564 in words is "four hundred ninety-one million, four hundred fifty-one thousand, five hundred sixty-four".