28475220 has 48 divisors (see below), whose sum is σ = 80176320. Its totient is φ = 7550976.

The previous prime is 28475203. The next prime is 28475261. The reversal of 28475220 is 2257482.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10351 + ... + 12809.

It is an arithmetic number, because the mean of its divisors is an integer number (1670340).

Almost surely, 2^28475220 is an apocalyptic number.

28475220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28475220 is an abundant number, since it is smaller than the sum of its proper divisors (51701100).

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

28475220 is a wasteful number, since it uses less digits than its factorization.

28475220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2664 (or 2662 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 30.

The square root of 28475220 is about 5336.2177616735. The cubic root of 28475220 is about 305.3671829693.

The spelling of 28475220 in words is "twenty-eight million, four hundred seventy-five thousand, two hundred twenty".