491533820 has 24 divisors (see below), whose sum is σ = 1046364144. Its totient is φ = 193919616.

The previous prime is 491533811. The next prime is 491533837. The reversal of 491533820 is 28335194.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 166874 + ... + 169793.

It is an arithmetic number, because the mean of its divisors is an integer number (43598506).

Almost surely, 2^491533820 is an apocalyptic number.

It is an amenable number.

491533820 is an abundant number, since it is smaller than the sum of its proper divisors (554830324).

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

491533820 is a wasteful number, since it uses less digits than its factorization.

491533820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336749 (or 336747 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 491533820 is about 22170.5620136252. The cubic root of 491533820 is about 789.1952602118.

The spelling of 491533820 in words is "four hundred ninety-one million, five hundred thirty-three thousand, eight hundred twenty".