28020556 has 12 divisors (see below), whose sum is σ = 51920568. Its totient is φ = 13186112.

The previous prime is 28020541. The next prime is 28020569. The reversal of 28020556 is 65502082.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 205966 + ... + 206101.

It is an arithmetic number, because the mean of its divisors is an integer number (4326714).

Almost surely, 2^28020556 is an apocalyptic number.

It is an amenable number.

28020556 is a deficient number, since it is larger than the sum of its proper divisors (23900012).

28020556 is a wasteful number, since it uses less digits than its factorization.

28020556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412088 (or 412086 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 28020556 is about 5293.4446251944. Note that the first 3 decimals coincide. The cubic root of 28020556 is about 303.7331886805.

The spelling of 28020556 in words is "twenty-eight million, twenty thousand, five hundred fifty-six".