988989 has 4 divisors (see below), whose sum is σ = 1318656. Its totient is φ = 659324.

The previous prime is 988979. The next prime is 989011. The reversal of 988989 is 989889.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 988989 - 2⁷ = 988861 is a prime.

It is a D-number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (988909) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 164829 + ... + 164834.

It is an arithmetic number, because the mean of its divisors is an integer number (329664).

2⁹⁸⁸⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

988989 is a deficient number, since it is larger than the sum of its proper divisors (329667).

988989 is a wasteful number, since it uses less digits than its factorization.

988989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329666.

The product of its digits is 373248, while the sum is 51.

The square root of 988989 is about 994.4792607189. The cubic root of 988989 is about 99.6316112303.

Subtracting 988989 from its reverse (989889), we obtain a square (900 = 30²).

The spelling of 988989 in words is "nine hundred eighty-eight thousand, nine hundred eighty-nine".