28673428 has 24 divisors (see below), whose sum is σ = 58520000. Its totient is φ = 12288024.

The previous prime is 28673377. The next prime is 28673443. The reversal of 28673428 is 82437682.

It is a congruent number.

It is an unprimeable number.

It is an upside-down number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9078 + ... + 11821.

Almost surely, 2^28673428 is an apocalyptic number.

28673428 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28673428 is an abundant number, since it is smaller than the sum of its proper divisors (29846572).

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

28673428 is a wasteful number, since it uses less digits than its factorization.

28673428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20924 (or 20908 counting only the distinct ones).

The product of its digits is 129024, while the sum is 40.

The square root of 28673428 is about 5354.7575108496. The cubic root of 28673428 is about 306.0740703827.

The spelling of 28673428 in words is "twenty-eight million, six hundred seventy-three thousand, four hundred twenty-eight".