20181228 has 24 divisors (see below), whose sum is σ = 47201280. Its totient is φ = 6711120.

The previous prime is 20181223. The next prime is 20181229. The reversal of 20181228 is 82218102.

It is a junction number, because it is equal to n+sod(n) for n = 20181198 and 20181207.

It is not an unprimeable number, because it can be changed into a prime (20181223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3993 + ... + 7503.

It is an arithmetic number, because the mean of its divisors is an integer number (1966720).

Almost surely, 2^20181228 is an apocalyptic number.

It is an amenable number.

20181228 is an abundant number, since it is smaller than the sum of its proper divisors (27020052).

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

20181228 is a wasteful number, since it uses less digits than its factorization.

20181228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3997 (or 3995 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 24.

The square root of 20181228 is about 4492.3521678515. The cubic root of 20181228 is about 272.2591784217.

The spelling of 20181228 in words is "twenty million, one hundred eighty-one thousand, two hundred twenty-eight".