491356661760 has 384 divisors, whose sum is σ = 1822582944000. Its totient is φ = 125329932288.

The previous prime is 491356661759. The next prime is 491356661797. The reversal of 491356661760 is 67166653194.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 491356661697 and 491356661706.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6320406 + ... + 6397674.

It is an arithmetic number, because the mean of its divisors is an integer number (4746309750).

Almost surely, 2^491356661760 is an apocalyptic number.

491356661760 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 491356661760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (911291472000).

491356661760 is an abundant number, since it is smaller than the sum of its proper divisors (1331226282240).

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

491356661760 is a wasteful number, since it uses less digits than its factorization.

491356661760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77328 (or 77302 counting only the distinct ones).

The product of its (nonzero) digits is 4898880, while the sum is 54.

The spelling of 491356661760 in words is "four hundred ninety-one billion, three hundred fifty-six million, six hundred sixty-one thousand, seven hundred sixty".