28178684441 has 4 divisors (see below), whose sum is σ = 29836254132. Its totient is φ = 26521114752.

The previous prime is 28178684431. The next prime is 28178684459. The reversal of 28178684441 is 14448687182.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12660750400 + 15517934041 = 112520^2 + 124571^2 .

It is a cyclic number.

It is not a de Polignac number, because 28178684441 - 2⁶ = 28178684377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28178684411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 828784820 + ... + 828784853.

It is an arithmetic number, because the mean of its divisors is an integer number (7459063533).

Almost surely, 2^28178684441 is an apocalyptic number.

It is an amenable number.

28178684441 is a deficient number, since it is larger than the sum of its proper divisors (1657569691).

28178684441 is a wasteful number, since it uses less digits than its factorization.

28178684441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1657569690.

The product of its digits is 2752512, while the sum is 53.

The spelling of 28178684441 in words is "twenty-eight billion, one hundred seventy-eight million, six hundred eighty-four thousand, four hundred forty-one".