491172120 has 128 divisors (see below), whose sum is σ = 1643601600. Its totient is φ = 130470912.

The previous prime is 491172047. The next prime is 491172127. The reversal of 491172120 is 21271194.

491172120 is a `hidden beast` number, since 491 + 172 + 1 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491172127) 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 31 ways as a sum of consecutive naturals, for example, 337314 + ... + 338766.

Almost surely, 2^491172120 is an apocalyptic number.

491172120 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 491172120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (821800800).

491172120 is an abundant number, since it is smaller than the sum of its proper divisors (1152429480).

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

491172120 is a wasteful number, since it uses less digits than its factorization.

491172120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1786 (or 1776 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 491172120 is about 22162.4032992814. The cubic root of 491172120 is about 789.0016336764.

The spelling of 491172120 in words is "four hundred ninety-one million, one hundred seventy-two thousand, one hundred twenty".