28138838 has 36 divisors (see below), whose sum is σ = 53198100. Its totient is φ = 11125296.

The previous prime is 28138837. The next prime is 28138843. The reversal of 28138838 is 83883182.

It is a junction number, because it is equal to n+sod(n) for n = 28138795 and 28138804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28138837) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 15713 + ... + 17411.

It is an arithmetic number, because the mean of its divisors is an integer number (1477725).

Almost surely, 2^28138838 is an apocalyptic number.

28138838 is a deficient number, since it is larger than the sum of its proper divisors (25059262).

28138838 is a wasteful number, since it uses less digits than its factorization.

28138838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1741 (or 1721 counting only the distinct ones).

The product of its digits is 73728, while the sum is 41.

The square root of 28138838 is about 5304.6053576114. The cubic root of 28138838 is about 304.1599674595.

The spelling of 28138838 in words is "twenty-eight million, one hundred thirty-eight thousand, eight hundred thirty-eight".