491377684240 has 80 divisors (see below), whose sum is σ = 1179751205376. Its totient is φ = 190138982400.

The previous prime is 491377684223. The next prime is 491377684307. The reversal of 491377684240 is 42486773194.

It is a tau number, because it is divible by the number of its divisors (80).

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 15 ways as a sum of consecutive naturals, for example, 6791455 + ... + 6863425.

Almost surely, 2^491377684240 is an apocalyptic number.

491377684240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 491377684240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (589875602688).

491377684240 is an abundant number, since it is smaller than the sum of its proper divisors (688373521136).

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

491377684240 is a wasteful number, since it uses less digits than its factorization.

491377684240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74768 (or 74762 counting only the distinct ones).

The product of its (nonzero) digits is 8128512, while the sum is 55.

It can be divided in two parts, 49137 and 7684240, that added together give a palindrome (7733377).

The spelling of 491377684240 in words is "four hundred ninety-one billion, three hundred seventy-seven million, six hundred eighty-four thousand, two hundred forty".