21033228 has 24 divisors (see below), whose sum is σ = 51661120. Its totient is φ = 6642000.

The previous prime is 21033223. The next prime is 21033239. The reversal of 21033228 is 82233012.

It is not an unprimeable number, because it can be changed into a prime (21033223) 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, 45898 + ... + 46353.

Almost surely, 2^21033228 is an apocalyptic number.

It is an amenable number.

21033228 is an abundant number, since it is smaller than the sum of its proper divisors (30627892).

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

21033228 is a wasteful number, since it uses less digits than its factorization.

21033228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92277 (or 92275 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21033228 is about 4586.1997339846. The cubic root of 21033228 is about 276.0378545012.

The spelling of 21033228 in words is "twenty-one million, thirty-three thousand, two hundred twenty-eight".