491335563264 has 768 divisors, whose sum is σ = 1673823191040. Its totient is φ = 124730081280.

The previous prime is 491335563233. The next prime is 491335563293. The reversal of 491335563264 is 462365533194.

It is a tau number, because it is divible by the number of its divisors (768).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2572437409 + ... + 2572437599.

It is an arithmetic number, because the mean of its divisors is an integer number (2179457280).

Almost surely, 2^491335563264 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 491335563264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (836911595520).

491335563264 is an abundant number, since it is smaller than the sum of its proper divisors (1182487627776).

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

491335563264 is a wasteful number, since it uses less digits than its factorization.

491335563264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386 (or 366 counting only the distinct ones).

The product of its digits is 6998400, while the sum is 51.

The spelling of 491335563264 in words is "four hundred ninety-one billion, three hundred thirty-five million, five hundred sixty-three thousand, two hundred sixty-four".