28143361 has 4 divisors (see below), whose sum is σ = 28195924. Its totient is φ = 28090800.

The previous prime is 28143331. The next prime is 28143373. The reversal of 28143361 is 16334182.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16334182 = 2 ⋅8167091.

It can be written as a sum of positive squares in 2 ways, for example, as 12390400 + 15752961 = 3520^2 + 3969^2 .

It is a cyclic number.

It is not a de Polignac number, because 28143361 - 2²³ = 19754753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28143331) 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, 25470 + ... + 26551.

It is an arithmetic number, because the mean of its divisors is an integer number (7048981).

Almost surely, 2^28143361 is an apocalyptic number.

It is an amenable number.

28143361 is a deficient number, since it is larger than the sum of its proper divisors (52563).

28143361 is an equidigital number, since it uses as much as digits as its factorization.

28143361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52562.

The product of its digits is 3456, while the sum is 28.

The square root of 28143361 is about 5305.0316681430. The cubic root of 28143361 is about 304.1762633448.

The spelling of 28143361 in words is "twenty-eight million, one hundred forty-three thousand, three hundred sixty-one".