9991098 has 24 divisors (see below), whose sum is σ = 23313108. Its totient is φ = 3074112.

The previous prime is 9991067. The next prime is 9991123. The reversal of 9991098 is 8901999.

It can be written as a sum of positive squares in 2 ways, for example, as 8485569 + 1505529 = 2913^2 + 1227^2 .

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 in 11 ways as a sum of consecutive naturals, for example, 21115 + ... + 21582.

Almost surely, 2^9991098 is an apocalyptic number.

9991098 is an abundant number, since it is smaller than the sum of its proper divisors (13322010).

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

9991098 is a wasteful number, since it uses less digits than its factorization.

9991098 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42718 (or 42715 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 45.

The square root of 9991098 is about 3160.8698169966. The cubic root of 9991098 is about 215.3795207652.

The spelling of 9991098 in words is "nine million, nine hundred ninety-one thousand, ninety-eight".