491395920 has 80 divisors (see below), whose sum is σ = 1589576832. Its totient is φ = 125340160.

The previous prime is 491395909. The next prime is 491395921. The reversal of 491395920 is 29593194.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491395921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38991 + ... + 50030.

Almost surely, 2^491395920 is an apocalyptic number.

491395920 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

491395920 is an abundant number, since it is smaller than the sum of its proper divisors (1098180912).

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

491395920 is a wasteful number, since it uses less digits than its factorization.

491395920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89060 (or 89054 counting only the distinct ones).

The product of its (nonzero) digits is 87480, while the sum is 42.

The square root of 491395920 is about 22167.4518156688. The cubic root of 491395920 is about 789.1214502989.

The spelling of 491395920 in words is "four hundred ninety-one million, three hundred ninety-five thousand, nine hundred twenty".