28443911 has 4 divisors (see below), whose sum is σ = 28593024. Its totient is φ = 28294800.

The previous prime is 28443901. The next prime is 28443913. The reversal of 28443911 is 11934482.

It is a happy number.

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 28443911 - 2²² = 24249607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28443913) 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, 74270 + ... + 74651.

It is an arithmetic number, because the mean of its divisors is an integer number (7148256).

Almost surely, 2^28443911 is an apocalyptic number.

28443911 is a deficient number, since it is larger than the sum of its proper divisors (149113).

28443911 is a wasteful number, since it uses less digits than its factorization.

28443911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149112.

The product of its digits is 6912, while the sum is 32.

The square root of 28443911 is about 5333.2833226822. The cubic root of 28443911 is about 305.2552230811.

The spelling of 28443911 in words is "twenty-eight million, four hundred forty-three thousand, nine hundred eleven".