28404443 has 4 divisors (see below), whose sum is σ = 28421568. Its totient is φ = 28387320.

The previous prime is 28404407. The next prime is 28404451. The reversal of 28404443 is 34440482.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34440482 = 2 ⋅17220241.

It is a cyclic number.

It is not a de Polignac number, because 28404443 - 2¹⁸ = 28142299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28404043) 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, 5771 + ... + 9492.

It is an arithmetic number, because the mean of its divisors is an integer number (7105392).

Almost surely, 2^28404443 is an apocalyptic number.

28404443 is a deficient number, since it is larger than the sum of its proper divisors (17125).

28404443 is a wasteful number, since it uses less digits than its factorization.

28404443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17124.

The product of its (nonzero) digits is 12288, while the sum is 29.

The square root of 28404443 is about 5329.5818785342. The cubic root of 28404443 is about 305.1139697697.

The spelling of 28404443 in words is "twenty-eight million, four hundred four thousand, four hundred forty-three".