28138841 has 8 divisors (see below), whose sum is σ = 28481544. Its totient is φ = 27798400.

The previous prime is 28138837. The next prime is 28138843. The reversal of 28138841 is 14883182.

It can be written as a sum of positive squares in 4 ways, for example, as 17673616 + 10465225 = 4204^2 + 3235^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28138841 - 2² = 28138837 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28138843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39791 + ... + 40491.

It is an arithmetic number, because the mean of its divisors is an integer number (3560193).

Almost surely, 2^28138841 is an apocalyptic number.

It is an amenable number.

28138841 is a deficient number, since it is larger than the sum of its proper divisors (342703).

28138841 is a wasteful number, since it uses less digits than its factorization.

28138841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1131.

The product of its digits is 12288, while the sum is 35.

The square root of 28138841 is about 5304.6056403846. The cubic root of 28138841 is about 304.1599782687.

The spelling of 28138841 in words is "twenty-eight million, one hundred thirty-eight thousand, eight hundred forty-one".