998644 has 12 divisors (see below), whose sum is σ = 1808100. Its totient is φ = 482048.

The previous prime is 998633. The next prime is 998651. The reversal of 998644 is 446899.

It can be written as a sum of positive squares in 2 ways, for example, as 374544 + 624100 = 612^2 + 790^2 .

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 998597 and 998606.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 4189 + ... + 4420.

It is an arithmetic number, because the mean of its divisors is an integer number (150675).

2⁹⁹⁸⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

998644 is a deficient number, since it is larger than the sum of its proper divisors (809456).

998644 is a wasteful number, since it uses less digits than its factorization.

998644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8642 (or 8640 counting only the distinct ones).

The product of its digits is 62208, while the sum is 40.

The square root of 998644 is about 999.3217700020. The cubic root of 998644 is about 99.9547795542.

The spelling of 998644 in words is "nine hundred ninety-eight thousand, six hundred forty-four".