9990998 has 16 divisors (see below), whose sum is σ = 15837120. Its totient is φ = 4714056.

The previous prime is 9990997. The next prime is 9991027. The reversal of 9990998 is 8990999.

It is a happy number.

9990998 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9990997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17465 + ... + 18027.

It is an arithmetic number, because the mean of its divisors is an integer number (989820).

Almost surely, 2^9990998 is an apocalyptic number.

9990998 is a deficient number, since it is larger than the sum of its proper divisors (5846122).

9990998 is a wasteful number, since it uses less digits than its factorization.

9990998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1051.

The product of its (nonzero) digits is 472392, while the sum is 53.

The square root of 9990998 is about 3160.8539985263. The cubic root of 9990998 is about 215.3788021914.

Subtracting from 9990998 its reverse (8990999), we obtain a palindrome (999999).

The spelling of 9990998 in words is "nine million, nine hundred ninety thousand, nine hundred ninety-eight".