491620431421440 has 560 divisors, whose sum is σ = 1819296081187200. Its totient is φ = 126869762211840.

The previous prime is 491620431421429. The next prime is 491620431421447. The reversal of 491620431421440 is 44124134026194.

491620431421440 is a `hidden beast` number, since 4 + 9 + 1 + 6 + 20 + 43 + 142 + 1 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491620431421447) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 100460586 + ... + 105240534.

It is an arithmetic number, because the mean of its divisors is an integer number (3248743002120).

Almost surely, 2^{491620431421440} is an apocalyptic number.

491620431421440 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 491620431421440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (909648040593600).

491620431421440 is an abundant number, since it is smaller than the sum of its proper divisors (1327675649765760).

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

491620431421440 is an equidigital number, since it uses as much as digits as its factorization.

491620431421440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4780023 (or 4779990 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 45.

The spelling of 491620431421440 in words is "four hundred ninety-one trillion, six hundred twenty billion, four hundred thirty-one million, four hundred twenty-one thousand, four hundred forty".