28438305 has 16 divisors (see below), whose sum is σ = 52001664. Its totient is φ = 13000320.

The previous prime is 28438303. The next prime is 28438321. The reversal of 28438305 is 50383482.

It is not a de Polignac number, because 28438305 - 2¹ = 28438303 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28438303) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135316 + ... + 135525.

It is an arithmetic number, because the mean of its divisors is an integer number (3250104).

Almost surely, 2^28438305 is an apocalyptic number.

It is an amenable number.

28438305 is a deficient number, since it is larger than the sum of its proper divisors (23563359).

28438305 is a wasteful number, since it uses less digits than its factorization.

28438305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270856.

The product of its (nonzero) digits is 23040, while the sum is 33.

The square root of 28438305 is about 5332.7577293554. The cubic root of 28438305 is about 305.2351675501.

The spelling of 28438305 in words is "twenty-eight million, four hundred thirty-eight thousand, three hundred five".