491518 has 4 divisors (see below), whose sum is σ = 737280. Its totient is φ = 245758.

The previous prime is 491503. The next prime is 491527. The reversal of 491518 is 815194.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

491518 is an untouchable number, because it is not equal to the sum of proper divisors of any 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 as a sum of consecutive naturals, namely, 122878 + ... + 122881.

It is an arithmetic number, because the mean of its divisors is an integer number (184320).

2⁴⁹¹⁵¹⁸ is an apocalyptic number.

491518 is a deficient number, since it is larger than the sum of its proper divisors (245762).

491518 is a wasteful number, since it uses less digits than its factorization.

491518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245761.

The product of its digits is 1440, while the sum is 28.

The square root of 491518 is about 701.0834472443. The cubic root of 491518 is about 78.9186793380.

The spelling of 491518 in words is "four hundred ninety-one thousand, five hundred eighteen".