28173222 has 48 divisors (see below), whose sum is σ = 76108032. Its totient is φ = 7317360.

The previous prime is 28173209. The next prime is 28173227. The reversal of 28173222 is 22237182.

It is a happy number.

It is a super-2 number, since 2×28173222² = 1587460875722568, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28173227) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8778 + ... + 11549.

It is an arithmetic number, because the mean of its divisors is an integer number (1585584).

Almost surely, 2^28173222 is an apocalyptic number.

28173222 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

28173222 is an abundant number, since it is smaller than the sum of its proper divisors (47934810).

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

28173222 is a wasteful number, since it uses less digits than its factorization.

28173222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20353 (or 20350 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 28173222 is about 5307.8453255535. The cubic root of 28173222 is about 304.2838055444.

The spelling of 28173222 in words is "twenty-eight million, one hundred seventy-three thousand, two hundred twenty-two".