28668428 has 12 divisors (see below), whose sum is σ = 51788352. Its totient is φ = 13871760.

The previous prime is 28668427. The next prime is 28668469. The reversal of 28668428 is 82486682.

It is not an unprimeable number, because it can be changed into a prime (28668421) 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, 115475 + ... + 115722.

It is an arithmetic number, because the mean of its divisors is an integer number (4315696).

Almost surely, 2^28668428 is an apocalyptic number.

It is an amenable number.

28668428 is a deficient number, since it is larger than the sum of its proper divisors (23119924).

28668428 is a wasteful number, since it uses less digits than its factorization.

28668428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231232 (or 231230 counting only the distinct ones).

The product of its digits is 294912, while the sum is 44.

The square root of 28668428 is about 5354.2906159453. The cubic root of 28668428 is about 306.0562785405.

The spelling of 28668428 in words is "twenty-eight million, six hundred sixty-eight thousand, four hundred twenty-eight".