28088220 has 24 divisors (see below), whose sum is σ = 78647184. Its totient is φ = 7490176.

The previous prime is 28088219. The next prime is 28088227. The reversal of 28088220 is 2288082.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28088227) 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, 234009 + ... + 234128.

It is an arithmetic number, because the mean of its divisors is an integer number (3276966).

Almost surely, 2^28088220 is an apocalyptic number.

28088220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28088220 is an abundant number, since it is smaller than the sum of its proper divisors (50558964).

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

28088220 is a wasteful number, since it uses less digits than its factorization.

28088220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468149 (or 468147 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 30.

The square root of 28088220 is about 5299.8320728114. The cubic root of 28088220 is about 303.9774769786.

The spelling of 28088220 in words is "twenty-eight million, eighty-eight thousand, two hundred twenty".