998709 has 4 divisors (see below), whose sum is σ = 1331616. Its totient is φ = 665804.

The previous prime is 998689. The next prime is 998717. The reversal of 998709 is 907899.

It is a happy number.

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 998709 - 2⁹ = 998197 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 (998749) 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, 166449 + ... + 166454.

It is an arithmetic number, because the mean of its divisors is an integer number (332904).

2⁹⁹⁸⁷⁰⁹ is an apocalyptic number.

It is an amenable number.

998709 is a deficient number, since it is larger than the sum of its proper divisors (332907).

998709 is a wasteful number, since it uses less digits than its factorization.

998709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332906.

The product of its (nonzero) digits is 40824, while the sum is 42.

The square root of 998709 is about 999.3542915303. The cubic root of 998709 is about 99.9569481347.

The spelling of 998709 in words is "nine hundred ninety-eight thousand, seven hundred nine".