28090045 has 4 divisors (see below), whose sum is σ = 33708060. Its totient is φ = 22472032.

The previous prime is 28090039. The next prime is 28090081. The reversal of 28090045 is 54009082.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54009082 = 2 ⋅27004541.

It can be written as a sum of positive squares in 2 ways, for example, as 6911641 + 21178404 = 2629^2 + 4602^2 .

It is a cyclic number.

It is not a de Polignac number, because 28090045 - 2⁷ = 28089917 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28089995 and 28090022.

It is a congruent number.

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, 2809000 + ... + 2809009.

It is an arithmetic number, because the mean of its divisors is an integer number (8427015).

Almost surely, 2^28090045 is an apocalyptic number.

It is an amenable number.

28090045 is a deficient number, since it is larger than the sum of its proper divisors (5618015).

28090045 is an equidigital number, since it uses as much as digits as its factorization.

28090045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5618014.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 28090045 is about 5300.0042452813. The cubic root of 28090045 is about 303.9840603658.

The spelling of 28090045 in words is "twenty-eight million, ninety thousand, forty-five".