491771280 has 640 divisors, whose sum is σ = 2159861760. Its totient is φ = 89210880.

The previous prime is 491771237. The next prime is 491771309. The reversal of 491771280 is 82177194.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 5525476 + ... + 5525564.

It is an arithmetic number, because the mean of its divisors is an integer number (3374784).

Almost surely, 2^491771280 is an apocalyptic number.

491771280 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 491771280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1079930880).

491771280 is an abundant number, since it is smaller than the sum of its proper divisors (1668090480).

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

491771280 is a wasteful number, since it uses less digits than its factorization.

491771280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 153 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 39.

The square root of 491771280 is about 22175.9166665101. The cubic root of 491771280 is about 789.3223265017.

The spelling of 491771280 in words is "four hundred ninety-one million, seven hundred seventy-one thousand, two hundred eighty".