491998 has 16 divisors (see below), whose sum is σ = 806400. Its totient is φ = 223776.

The previous prime is 491983. The next prime is 492007. The reversal of 491998 is 899194.

It is a self number, because there is not a number n which added to its sum of digits gives 491998.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3228 + ... + 3376.

It is an arithmetic number, because the mean of its divisors is an integer number (50400).

2⁴⁹¹⁹⁹⁸ is an apocalyptic number.

491998 is a deficient number, since it is larger than the sum of its proper divisors (314402).

491998 is a wasteful number, since it uses less digits than its factorization.

491998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291.

The product of its digits is 23328, while the sum is 40.

The square root of 491998 is about 701.4256910037. The cubic root of 491998 is about 78.9443607587.

The spelling of 491998 in words is "four hundred ninety-one thousand, nine hundred ninety-eight".