28388738 has 32 divisors (see below), whose sum is σ = 51408000. Its totient is φ = 11738832.

The previous prime is 28388713. The next prime is 28388741. The reversal of 28388738 is 83788382.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28388692 and 28388701.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 19181 + ... + 20607.

It is an arithmetic number, because the mean of its divisors is an integer number (1606500).

Almost surely, 2^28388738 is an apocalyptic number.

28388738 is a deficient number, since it is larger than the sum of its proper divisors (23019262).

28388738 is a wasteful number, since it uses less digits than its factorization.

28388738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1479 (or 1465 counting only the distinct ones).

The product of its digits is 516096, while the sum is 47.

The square root of 28388738 is about 5328.1082946952. The cubic root of 28388738 is about 305.0577262411.

The spelling of 28388738 in words is "twenty-eight million, three hundred eighty-eight thousand, seven hundred thirty-eight".