28728045 has 54 divisors (see below), whose sum is σ = 54046122. Its totient is φ = 14113536.

The previous prime is 28728023. The next prime is 28728061. The reversal of 28728045 is 54082782.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 9622404 + 19105641 = 3102^2 + 4371^2 .

It is not a de Polignac number, because 28728045 - 2⁵ = 28728013 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 611212 + ... + 611258.

Almost surely, 2^28728045 is an apocalyptic number.

It is an amenable number.

28728045 is a deficient number, since it is larger than the sum of its proper divisors (25318077).

28728045 is a wasteful number, since it uses less digits than its factorization.

28728045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 36.

The square root of 28728045 is about 5359.8549420670. The cubic root of 28728045 is about 306.2682832344.

The spelling of 28728045 in words is "twenty-eight million, seven hundred twenty-eight thousand, forty-five".