491521884 has 96 divisors (see below), whose sum is σ = 1405716480. Its totient is φ = 130470912.

The previous prime is 491521879. The next prime is 491521951. The reversal of 491521884 is 488125194.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

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, 110634 + ... + 114990.

It is an arithmetic number, because the mean of its divisors is an integer number (14642880).

Almost surely, 2^491521884 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 491521884, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (702858240).

491521884 is an abundant number, since it is smaller than the sum of its proper divisors (914194596).

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

491521884 is a wasteful number, since it uses less digits than its factorization.

491521884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4467 (or 4465 counting only the distinct ones).

The product of its digits is 92160, while the sum is 42.

The square root of 491521884 is about 22170.2928262123. The cubic root of 491521884 is about 789.1888721055.

The spelling of 491521884 in words is "four hundred ninety-one million, five hundred twenty-one thousand, eight hundred eighty-four".