28208220 has 48 divisors (see below), whose sum is σ = 79366560. Its totient is φ = 7485696.

The previous prime is 28208207. The next prime is 28208227. The reversal of 28208220 is 2280282.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28208227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12714 + ... + 14766.

It is an arithmetic number, because the mean of its divisors is an integer number (1653470).

Almost surely, 2^28208220 is an apocalyptic number.

28208220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28208220 is an abundant number, since it is smaller than the sum of its proper divisors (51158340).

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

28208220 is a wasteful number, since it uses less digits than its factorization.

28208220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2294 (or 2292 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 24.

The square root of 28208220 is about 5311.1411203243. The cubic root of 28208220 is about 304.4097515932.

The spelling of 28208220 in words is "twenty-eight million, two hundred eight thousand, two hundred twenty".