491804181 has 48 divisors (see below), whose sum is σ = 805109760. Its totient is φ = 286596000.

The previous prime is 491804177. The next prime is 491804191. The reversal of 491804181 is 181408194.

It is not a de Polignac number, because 491804181 - 2² = 491804177 is a prime.

It is a super-2 number, since 2×491804181² = 483742704898161522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491804191) 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 47 ways as a sum of consecutive naturals, for example, 585760 + ... + 586598.

It is an arithmetic number, because the mean of its divisors is an integer number (16773120).

Almost surely, 2^491804181 is an apocalyptic number.

It is an amenable number.

491804181 is a deficient number, since it is larger than the sum of its proper divisors (313305579).

491804181 is a wasteful number, since it uses less digits than its factorization.

491804181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1078 (or 1075 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 491804181 is about 22176.6584723668. The cubic root of 491804181 is about 789.3399288003.

It can be divided in two parts, 49180 and 4181, that added together give a square (53361 = 231²).

The spelling of 491804181 in words is "four hundred ninety-one million, eight hundred four thousand, one hundred eighty-one".