28728090 has 24 divisors (see below), whose sum is σ = 74693268. Its totient is φ = 7660800.

The previous prime is 28728083. The next prime is 28728097. The reversal of 28728090 is 9082782.

It is an interprime number because it is at equal distance from previous prime (28728083) and next prime (28728097).

It can be written as a sum of positive squares in 2 ways, for example, as 23011209 + 5716881 = 4797^2 + 2391^2 .

It is not an unprimeable number, because it can be changed into a prime (28728097) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 159511 + ... + 159690.

Almost surely, 2^28728090 is an apocalyptic number.

28728090 is an abundant number, since it is smaller than the sum of its proper divisors (45965178).

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

28728090 is a wasteful number, since it uses less digits than its factorization.

28728090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319214 (or 319211 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 28728090 is about 5359.8591399402. The cubic root of 28728090 is about 306.2684431486.

The spelling of 28728090 in words is "twenty-eight million, seven hundred twenty-eight thousand, ninety".