28103728 has 10 divisors (see below), whose sum is σ = 54451004. Its totient is φ = 14051856.

The previous prime is 28103711. The next prime is 28103729. The reversal of 28103728 is 82730182.

It is a self number, because there is not a number n which added to its sum of digits gives 28103728.

It is not an unprimeable number, because it can be changed into a prime (28103729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 878226 + ... + 878257.

Almost surely, 2^28103728 is an apocalyptic number.

It is an amenable number.

28103728 is a deficient number, since it is larger than the sum of its proper divisors (26347276).

28103728 is a wasteful number, since it uses less digits than its factorization.

28103728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1756491 (or 1756485 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 28103728 is about 5301.2949361453. The cubic root of 28103728 is about 304.0334104554.

The spelling of 28103728 in words is "twenty-eight million, one hundred three thousand, seven hundred twenty-eight".