28194643 has 4 divisors (see below), whose sum is σ = 28227528. Its totient is φ = 28161760.

The previous prime is 28194637. The next prime is 28194667. The reversal of 28194643 is 34649182.

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

It is a cyclic number.

It is not a de Polignac number, because 28194643 - 2¹³ = 28186451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28194623) 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, 15121 + ... + 16882.

It is an arithmetic number, because the mean of its divisors is an integer number (7056882).

Almost surely, 2^28194643 is an apocalyptic number.

28194643 is a deficient number, since it is larger than the sum of its proper divisors (32885).

28194643 is an equidigital number, since it uses as much as digits as its factorization.

28194643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32884.

The product of its digits is 41472, while the sum is 37.

The square root of 28194643 is about 5309.8628042540. The cubic root of 28194643 is about 304.3609049041.

The spelling of 28194643 in words is "twenty-eight million, one hundred ninety-four thousand, six hundred forty-three".