9988 has 12 divisors (see below), whose sum is σ = 19152. Its totient is φ = 4520.

The previous prime is 9973. The next prime is 10007. The reversal of 9988 is 8899.

9988 = T₃₇ + T₃₈ + ... + T₄₇.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is an unprimeable number.

9988 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 (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70 + ... + 157.

It is an arithmetic number, because the mean of its divisors is an integer number (1596).

2⁹⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

9988 is a deficient number, since it is larger than the sum of its proper divisors (9164).

9988 is a wasteful number, since it uses less digits than its factorization.

9988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242 (or 240 counting only the distinct ones).

The product of its digits is 5184, while the sum is 34.

The square root of 9988 is about 99.9399819892. The cubic root of 9988 is about 21.5357257122.

Subtracting from 9988 its reverse (8899), we obtain a square (1089 = 33²).

The spelling of 9988 in words is "nine thousand, nine hundred eighty-eight".