28221030 has 24 divisors (see below), whose sum is σ = 73374912. Its totient is φ = 7525584.

The previous prime is 28220999. The next prime is 28221049. The reversal of 28221030 is 3012282.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 28220994 and 28221012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 156694 + ... + 156873.

It is an arithmetic number, because the mean of its divisors is an integer number (3057288).

Almost surely, 2^28221030 is an apocalyptic number.

28221030 is an abundant number, since it is smaller than the sum of its proper divisors (45153882).

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

28221030 is a wasteful number, since it uses less digits than its factorization.

28221030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313580 (or 313577 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 28221030 is about 5312.3469389715. The cubic root of 28221030 is about 304.4558244375.

It can be divided in two parts, 282 and 21030, that added together give a palindrome (21312).

The spelling of 28221030 in words is "twenty-eight million, two hundred twenty-one thousand, thirty".