990228 has 24 divisors (see below), whose sum is σ = 2328480. Its totient is φ = 327520.

The previous prime is 990211. The next prime is 990239. The reversal of 990228 is 822099.

It is a junction number, because it is equal to n+sod(n) for n = 990195 and 990204.

It is a congruent number.

It is an unprimeable number.

990228 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 7 ways as a sum of consecutive naturals, for example, 1918 + ... + 2378.

It is an arithmetic number, because the mean of its divisors is an integer number (97020).

2⁹⁹⁰²²⁸ is an apocalyptic number.

It is an amenable number.

990228 is an abundant number, since it is smaller than the sum of its proper divisors (1338252).

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

990228 is a wasteful number, since it uses less digits than its factorization.

990228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 647 (or 645 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 990228 is about 995.1020048216. The cubic root of 990228 is about 99.6731998467.

The spelling of 990228 in words is "nine hundred ninety thousand, two hundred twenty-eight".