28420873 has 4 divisors (see below), whose sum is σ = 30607108. Its totient is φ = 26234640.

The previous prime is 28420867. The next prime is 28420883. The reversal of 28420873 is 37802482.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9784384 + 18636489 = 3128^2 + 4317^2 .

It is a cyclic number.

It is not a de Polignac number, because 28420873 - 2¹⁷ = 28289801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28420813) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1093098 + ... + 1093123.

It is an arithmetic number, because the mean of its divisors is an integer number (7651777).

Almost surely, 2^28420873 is an apocalyptic number.

It is an amenable number.

28420873 is a deficient number, since it is larger than the sum of its proper divisors (2186235).

28420873 is a wasteful number, since it uses less digits than its factorization.

28420873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2186234.

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 28420873 is about 5331.1230524159. The cubic root of 28420873 is about 305.1727875196.

The spelling of 28420873 in words is "twenty-eight million, four hundred twenty thousand, eight hundred seventy-three".