28920556 has 24 divisors (see below), whose sum is σ = 58637600. Its totient is φ = 12223872.

The previous prime is 28920547. The next prime is 28920571. The reversal of 28920556 is 65502982.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5031 + ... + 9118.

Almost surely, 2^28920556 is an apocalyptic number.

It is an amenable number.

28920556 is an abundant number, since it is smaller than the sum of its proper divisors (29717044).

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

28920556 is a wasteful number, since it uses less digits than its factorization.

28920556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14233 (or 14231 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 28920556 is about 5377.7835583073. The cubic root of 28920556 is about 306.9508775610.

The spelling of 28920556 in words is "twenty-eight million, nine hundred twenty thousand, five hundred fifty-six".