28740638 has 16 divisors (see below), whose sum is σ = 45009024. Its totient is φ = 13750560.

The previous prime is 28740637. The next prime is 28740667. The reversal of 28740638 is 83604782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28740637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1331 + ... + 7697.

It is an arithmetic number, because the mean of its divisors is an integer number (2813064).

Almost surely, 2^28740638 is an apocalyptic number.

28740638 is a deficient number, since it is larger than the sum of its proper divisors (16268386).

28740638 is a wasteful number, since it uses less digits than its factorization.

28740638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6467.

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 28740638 is about 5361.0295652981. The cubic root of 28740638 is about 306.3130278162.

The spelling of 28740638 in words is "twenty-eight million, seven hundred forty thousand, six hundred thirty-eight".