28728402 has 16 divisors (see below), whose sum is σ = 60836832. Its totient is φ = 9012800.

The previous prime is 28728383. The next prime is 28728443. The reversal of 28728402 is 20482782.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 140724 + ... + 140927.

It is an arithmetic number, because the mean of its divisors is an integer number (3802302).

Almost surely, 2^28728402 is an apocalyptic number.

28728402 is an abundant number, since it is smaller than the sum of its proper divisors (32108430).

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

28728402 is a wasteful number, since it uses less digits than its factorization.

28728402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281673.

The product of its (nonzero) digits is 14336, while the sum is 33.

The square root of 28728402 is about 5359.8882451036. Note that the first 3 decimals coincide. The cubic root of 28728402 is about 306.2695518824.

The spelling of 28728402 in words is "twenty-eight million, seven hundred twenty-eight thousand, four hundred two".