491172118 has 4 divisors (see below), whose sum is σ = 736758180. Its totient is φ = 245586058.

The previous prime is 491172047. The next prime is 491172127. The reversal of 491172118 is 811271194.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 811271194 = 2 ⋅405635597.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122793028 + ... + 122793031.

It is an arithmetic number, because the mean of its divisors is an integer number (184189545).

Almost surely, 2^491172118 is an apocalyptic number.

491172118 is a deficient number, since it is larger than the sum of its proper divisors (245586062).

491172118 is a wasteful number, since it uses less digits than its factorization.

491172118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245586061.

The product of its digits is 4032, while the sum is 34.

The square root of 491172118 is about 22162.4032541600. The cubic root of 491172118 is about 789.0016326055.

The spelling of 491172118 in words is "four hundred ninety-one million, one hundred seventy-two thousand, one hundred eighteen".