28904428 has 24 divisors (see below), whose sum is σ = 59155712. Its totient is φ = 12099024.

The previous prime is 28904419. The next prime is 28904429. The reversal of 28904428 is 82440982.

It is not an unprimeable number, because it can be changed into a prime (28904429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10800 + ... + 13207.

Almost surely, 2^28904428 is an apocalyptic number.

28904428 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28904428 is an abundant number, since it is smaller than the sum of its proper divisors (30251284).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28904428 is a wasteful number, since it uses less digits than its factorization.

28904428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24061 (or 24059 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 37.

The square root of 28904428 is about 5376.2838466733. The cubic root of 28904428 is about 306.8938082999.

The spelling of 28904428 in words is "twenty-eight million, nine hundred four thousand, four hundred twenty-eight".