28020243 has 4 divisors (see below), whose sum is σ = 37360328. Its totient is φ = 18680160.

The previous prime is 28020241. The next prime is 28020253. The reversal of 28020243 is 34202082.

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

It is not a de Polignac number, because 28020243 - 2¹ = 28020241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28020241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4670038 + ... + 4670043.

It is an arithmetic number, because the mean of its divisors is an integer number (9340082).

Almost surely, 2^28020243 is an apocalyptic number.

28020243 is a deficient number, since it is larger than the sum of its proper divisors (9340085).

28020243 is an equidigital number, since it uses as much as digits as its factorization.

28020243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9340084.

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 28020243 is about 5293.4150602423. The cubic root of 28020243 is about 303.7320577388.

The spelling of 28020243 in words is "twenty-eight million, twenty thousand, two hundred forty-three".