998556 has 48 divisors (see below), whose sum is σ = 2591904. Its totient is φ = 297216.

The previous prime is 998551. The next prime is 998561. The reversal of 998556 is 655899.

It is an interprime number because it is at equal distance from previous prime (998551) and next prime (998561).

It is a super-2 number, since 2×998556² = 1994228170272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (998551) by changing a digit.

998556 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5686 + ... + 5858.

It is an arithmetic number, because the mean of its divisors is an integer number (53998).

2⁹⁹⁸⁵⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 998556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1295952).

998556 is an abundant number, since it is smaller than the sum of its proper divisors (1593348).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

998556 is a wasteful number, since it uses less digits than its factorization.

998556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230 (or 228 counting only the distinct ones).

The product of its digits is 97200, while the sum is 42.

The square root of 998556 is about 999.2777391696. The cubic root of 998556 is about 99.9518434799.

The spelling of 998556 in words is "nine hundred ninety-eight thousand, five hundred fifty-six".