28381839 has 16 divisors (see below), whose sum is σ = 41568000. Its totient is φ = 17145216.

The previous prime is 28381831. The next prime is 28381841. The reversal of 28381839 is 93818382.

28381839 is nontrivially palindromic in base 13.

It is not a de Polignac number, because 28381839 - 2³ = 28381831 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28381839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28381831) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9514 + ... + 12135.

It is an arithmetic number, because the mean of its divisors is an integer number (2598000).

Almost surely, 2^28381839 is an apocalyptic number.

28381839 is a deficient number, since it is larger than the sum of its proper divisors (13186161).

28381839 is a wasteful number, since it uses less digits than its factorization.

28381839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21694.

The product of its digits is 82944, while the sum is 42.

The square root of 28381839 is about 5327.4608398373. The cubic root of 28381839 is about 305.0330126409.

The spelling of 28381839 in words is "twenty-eight million, three hundred eighty-one thousand, eight hundred thirty-nine".