28997443 has 4 divisors (see below), whose sum is σ = 29013448. Its totient is φ = 28981440.

The previous prime is 28997417. The next prime is 28997453. The reversal of 28997443 is 34479982.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34479982 = 2 ⋅17239991.

It is a cyclic number.

It is not a de Polignac number, because 28997443 - 2¹⁷ = 28866371 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28997393 and 28997402.

It is not an unprimeable number, because it can be changed into a prime (28997453) 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, 4878 + ... + 9043.

It is an arithmetic number, because the mean of its divisors is an integer number (7253362).

Almost surely, 2^28997443 is an apocalyptic number.

28997443 is a deficient number, since it is larger than the sum of its proper divisors (16005).

28997443 is a wasteful number, since it uses less digits than its factorization.

28997443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16004.

The product of its digits is 435456, while the sum is 46.

The square root of 28997443 is about 5384.9273904111. The cubic root of 28997443 is about 307.2226525168. Note that the first 3 decimals are identical.

The spelling of 28997443 in words is "twenty-eight million, nine hundred ninety-seven thousand, four hundred forty-three".