820228 has 18 divisors (see below), whose sum is σ = 1483034. Its totient is φ = 396864.

The previous prime is 820223. The next prime is 820231. The reversal of 820228 is 822028.

It can be written as a sum of positive squares in 3 ways, for example, as 304704 + 515524 = 552^2 + 718^2 .

It is a d-powerful number, because it can be written as 8⁵ + 2² + 2¹⁰ + 0 + 2¹⁹ + 8⁶ .

It is a junction number, because it is equal to n+sod(n) for n = 820199 and 820208.

It is not an unprimeable number, because it can be changed into a prime (820223) by changing a digit.

820228 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11200 + ... + 11272.

2⁸²⁰²²⁸ is an apocalyptic number.

It is an amenable number.

820228 is a deficient number, since it is larger than the sum of its proper divisors (662806).

820228 is a wasteful number, since it uses less digits than its factorization.

820228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183 (or 128 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 820228 is about 905.6643970037. The cubic root of 820228 is about 93.6076904583.

The spelling of 820228 in words is "eight hundred twenty thousand, two hundred twenty-eight".