991118 has 4 divisors (see below), whose sum is σ = 1486680. Its totient is φ = 495558.

The previous prime is 991091. The next prime is 991127. The reversal of 991118 is 811199.

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

It is a magnanimous number.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 247778 + ... + 247781.

It is an arithmetic number, because the mean of its divisors is an integer number (371670).

2⁹⁹¹¹¹⁸ is an apocalyptic number.

991118 is a deficient number, since it is larger than the sum of its proper divisors (495562).

991118 is a wasteful number, since it uses less digits than its factorization.

991118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495561.

The product of its digits is 648, while the sum is 29.

The square root of 991118 is about 995.5490947211. The cubic root of 991118 is about 99.7030524275.

The spelling of 991118 in words is "nine hundred ninety-one thousand, one hundred eighteen".